Armstrong Midlength Mk II X-Form Board
Sizes: ML38 / ML45 / ML55 / ML65 / ML75 / ML85 / ML100 / ML115 / ML130
RED = in demo
Need help? Book in a video call with Nick, and we can help determine if this is the right product for you, help you select the right size, and advise on trading valuations on your current gear.
Why Riders Are Choosing the Midlength Mk II
The Midlength Mk II is designed to make every stage of foiling easier and more intuitive.
The refined double concave to subtle V bottom helps generate lift efficiently during takeoff, while the thinner X-Form profile improves responsiveness once on foil. Touch-downs recover faster, the board tracks less when reconnecting with the water, and the surf-style squash tail improves stability during starts and low-speed manoeuvres.
Combined with Armstrong’s proven Forward Geometry foil track system, the result is a board that feels balanced, predictable, and remarkably connected.
Whether you’re progressing in parawing, wing foiling, Foil Drive, or downwind foiling, the Midlength Mk II gives riders the confidence to push further while making the learning process smoother and more enjoyable.
Key Specs
- New X-Form precision molded board technology
- Lighter, stiffer, and more durable construction
- Full high-density PVC wrap construction
- Dual carbon stringer system
- Carbon foil tracks integrated into stringers
- Forward Geometry foil track placement
- Refined thinner profile for improved foil connection
- Double concave to subtle V bottom design
- Surf-style squash tail for stability and early release
- Foil Assist compatible
- Protective board bag included
Why X-Form Matters
The Midlength Mk II isn’t just a new shape. It’s the first board built around Armstrong’s new X-Form Precision Molded Board Technology, developed to solve the durability, consistency, and performance limitations of traditional board construction.
The result is a board that is lighter, stronger, and significantly more resistant to long-term fatigue and softening.
For riders, that means the board you buy today is designed to feel the same hundreds of sessions from now.
The precision molded construction creates a stronger connection between rider and foil, delivering cleaner feedback underfoot, improved responsiveness, and greater confidence when conditions get challenging.
Economically, X-Form represents a significant investment in long-term durability. The full PVC wrapped construction, reinforced rails, integrated carbon foil tracks, and dual carbon stringer system are all designed to withstand years of progression while maintaining the board’s original ride characteristics.
In simple terms:
- More durability
- More consistency
- More confidence
- More value over the life of the board
Because performance means nothing if your gear doesn’t last.
How It Compares
Midlength Mk II vs Traditional Composite Foilboards
Midlength Mk II X-Form
- Significantly stiffer and more durable
- Precision molded for exact consistency
- Thinner profile with improved foil connection
- More resistant to softening and fatigue over time
- Cleaner release and reduced sticking on touch-downs
Traditional Composite Construction
- Softer flex over time
- Less consistent manufacturing tolerances
- Heavier for equivalent stiffness
- More prone to water absorption and fatigue
In simple terms:
- Midlength Mk II = connected, durable, precision performance
- Traditional construction = softer, less direct feel over time
Midlength Mk II Overview
The Armstrong Midlength Mk II introduces Armstrong’s new X-Form precision molded construction technology, delivering a major step forward in board stiffness, durability, and long-term consistency.
Built and refined in New Zealand’s demanding conditions, the Midlength Mk II combines efficient paddling, fast takeoffs, and a highly connected feel on foil with a lighter and stronger overall construction.
The thinner X-Form profile allows the rider to stand closer to the foil, improving responsiveness and reducing unwanted touch-downs. Combined with refined volume distribution and a surf-inspired outline, the result is a board that feels composed, intuitive, and highly predictable across a wide range of conditions.
X-Form Construction Technology
The new X-Form construction was developed to solve long-standing durability and consistency limitations found in traditional board manufacturing.
Key features include:
- CNC-machined precision molds
- Internal CNC-cut structural components
- Full PVC wrapped construction
- Dual carbon stringer system
- Integrated carbon foil tracks
- High-pressure molded layup
This creates a board that is:
- Stronger
- More consistent
- More rigid under load
- More resistant to fatigue over time
Unlike traditional molded boards, the X-Form process locks every component into place under uniform pressure and temperature with minimal distortion.
Shape & On-Water Feel
The Midlength Mk II has been refined to feel:
- Composed
- Responsive
- Predictable
The thinner profile and updated bottom design improve release during touch-downs while maintaining excellent stability during takeoff and paddling.
Key shape updates include:
- Double concave to subtle V bottom shape
- Shallower chines for reduced drag
- Surf-style squash tail for improved stability
- Forward Geometry foil track placement
- Reduced sticking and tracking during touchdowns
The result is a board that accelerates efficiently onto foil while maintaining a highly connected and intuitive feel once flying.
Real-World Performance
From our own testing and feedback:
- Noticeably more connected underfoot
- Faster release during touch-downs
- Improved stiffness and responsiveness
- Stable paddling and early takeoff performance
- Excellent efficiency on mid-length foil setups
The thinner profile creates a much more direct feeling between rider and foil, particularly when carving, pumping, or riding at speed.
Best For
- Mid-length foil setups
- Parawing progression
- Downwind foiling
- Wing foiling
- Efficient paddling and early takeoffs
- Riders prioritising stiffness and durability
Important Notes
The Midlength Mk II is not simply a shape update — it represents a completely new construction platform for Armstrong.
The new X-Form technology delivers significant gains in stiffness, consistency, and long-term durability while maintaining the connected riding feel Armstrong boards are known for.
Riders coming from traditional constructions will immediately notice:
- Improved rigidity
- Cleaner release
- More direct foil feedback
- Increased confidence at speed
Available at Underground Surf and Foil
- New Zealand’s leading Armstrong dealer
- New Zealand’s only official Armstrong demo centre
- Based at Orewa Beach, Auckland
We ride the full Armstrong board range and have demo equipment available. If you’re unsure which Midlength Mk II size suits your setup, we can help guide you toward the right board for your riding.
Talk to Us
Get in touch or book a demo to experience the Armstrong Midlength Mk II X-Form Board for yourself.
To View our second hand stock visit our Instagram "used Items" page HERE
Express Worldwide Shipping on Armstrong Foils:
Australia Free Express Shipping on Armstrong wings, wind wings and boards as part of a full kit or combo package. We are happy to change mast size, fuse size, rear wing on any kit. Armstrong Boards can be shipped on a case by case basis please contact Nick for a quote. If you are wanting a custom kit or have any questions contact nick@undergroundsurf.co.nz or call Nick on +64212891660 for a tailored quote.
Rest of World. Exclusive to Armstrong product only. Free shipping on all foils and wind wings minimum spend $750NZD. You can ONLY have Armstrong products in your cart. Minimum Spend $750NZD for free shipping. Boards are NOT free shipping unless as part of a full foil combo. Single Boards can be shipped but only on a case-by-case basis. Allow 7-21 Days for shipping depending on where you live. If you want a custom kit or have any questions, contact nick@undergroundsurf.co.nz or call Nick at +64212891660 for a tailored quote.
All prices on our website are in New Zealand Dollars. To view the exchange rate to USD:
https://www.xe.com/currencyconverter/convert/?Amount=1&From=NZD&To=USD
12 Months Interest-Free Finance with Q Card. Simple and Easy to apply. Find out more about this, plus Afterpay HERE.
Learn to foil: We'll take you from zero to HERO with our private foil lessons! Start on a massive 8'6" foil board being towed behind a jetski, as your skills develop we'll give you smaller boards to try. Two lessons are refundable with the purchase of any complete Armstrong foil combo (or one lesson refunded with the purchase of any wing & mast combo). Call or email nick@undergroundsurf.co.nz on +64212891660 to book your lesson today. We also have full demo range including A Wind Wings, Boards and Foils.
All orders will be shipped from Underground Skate Limited - 306 Hibiscus Coast Highway, Orewa, 0931
If you have any questions about shipping, then please email us on info@undergroundsurf.co.nz 9am - 3.30pm Weekdays or use our website chat feature and we'll be happy to help you out.
All items are packaged with extreme care, under CCTV surveillance. As freight is handled by third parties, we advise you to thoroughly inspect your Good(s) for damage in transit.
Parcels are not collected on weekends, so orders received after 1pm Friday will be shipped the following Monday otherwise 'click and collect' is available from our store. (Please confirm your order is ready before driving to the store.)
NEW ZEALAND:
CLICK & COLLECT is of course free from our store, just select this option at the checkout and you can collect during our stores opening hours.
For smaller items:
- $10 – NZ WIDE VIA ARAMEX (Non Rural)
- $15 - NZ WIDE VIA ARAMEX (Rural)
- $25 – NORTH ISLAND VIA NZ POST EXPRESS – excludes bulky* items.
- $50 - SOUTH ISLAND VIA NZ POST EXPRESS – excludes bulky* items.
Address Checker - Please check your address to avoid delays if you select non rural and you are rural https://www.addresscheck.co.nz
We use a standard Aramex Courier service to ship your goods nationwide, this is a non-signature service. We suggest under “Shipping Instructions” you leave a note as to where the courier should leave your parcel if you are not there on the day of delivery.
NZ POST EXPRESS – non-signature service, tracking will be sent directly from NZ Post when your order is booked with this service. Cut Off – 3.30pm Weekdays. We are unable to send bulky items via NZ Post.
You will receive an invoice and tracking number in an e-mail once your order is dispatched from Underground in Orewa Auckland. Once the order has been collected by our courier, your tracking number will be live.
*BULKY ITEMS – excludes all Complete Skateboards, Wide Brim Straw Hats, Surfboards, all Paddle Boards, all Board Bags, SUP Paddles, SUP Carts, Body Boards.
For Surfboards, Sups and larger items:
- $49.99 NZ WIDE – Surfboards & Foil Boards
- $99.99 NZ WIDE – Sups
Please note:
- Boards 7'2 and under will be delivered using Aramex Couriers, we advise getting it shipped to your closest Aramex depot where possible. You can check out the depots here - https://www.aramex.co.nz/contact-us/aramex-depot/
- Boards 7'4 and larger will be delivered to the nearest Titus Transport Depot or Depot Partner for you to collect. They have depots in most main centres throughout New Zealand. Or we can have them delivered direct to your door at your cost and can provide a shipping quote upon request.
For Shipping Costs on Surfboards, Foils & Sups direct to your own address please contact us via our Chat Feature or emails us on info@undergroundsurf.co.nz and we'll be happy to help you out.
Unfortunately, we are unable to deliver any large items such as Surfboards or SUPs to rural areas.
SURFBOARDS, SUPS and FOILS – please do not sign for your package if the packaging is damaged in anyway as Underground Surf will not be liable or any damages that are signed for and accepted on delivery.
All boards are packaged under CTV surveillance and are marked as Fragile with a “Do not sign for if Damaged” A4 note.
If you have any questions, please contact us via our Chat Feature or email us on info@undergroundsurf.co.nz and we'll be happy to help you out.
AUSTRALIA:
- FREE SHIPPING on Orders over $200.00 – excludes bulky* items.
- $29.99 on Orders under $200.00 – excludes bulky* items.
*BULKY ITEMS – excludes all Complete Skateboards, Wide Brim Straw Hats, Surfboards, all Paddle Boards, all Board Bags, SUP Paddles, SUP Carts, Body Boards.
We use a standard Aramex Courier service to ship your goods Australian wide, this is a non-signature service. We suggest under “Shipping Instructions” you leave a note as to where the courier should leave your parcel if you are not there on the day of delivery.
You will receive shipping notifications directly from Aramex once your parcel as been booked for collection.
All prices below and on our website are in New Zealand Dollars. To view the exchange rate - https://www.xe.com/currencyconverter/convert/?Amount=1&From=NZD&To=AUD
If you have any questions, please contact us via our Chat Feature or email us on info@undergroundskate.co.nz and we'll be happy to help you out.
REST OF THE WORLD:
At this stage we only ship internationally to Australia, but we can look into sending our products all over the world for you just email us on info@undergroundsurf.co.nz and we'll happily give you a quote.
CUSTOMS AND DUTY CHARGES:
If you are purchasing Internationally then we recommend that you review the following resource to assist you in calculating the charges you may be subject to upon arrival of your parcel to your country/local area: dutycalculator.com
International orders may be subject to local charges. Any customs or import duties and associated fees are charged once the parcel reaches its destination country. These charges must be paid by the recipient of the parcel. We have no control over these charges and cannot predict what they may be.
Underground Surf cannot be held responsible for any additional charges on your order, nor can we accept a return of the order in this case.
Customs policies vary widely from country to country, so please contact your local customs office for further information. If you refuse to pay these charges your parcel may be abandoned, and Underground Surf will not be held responsible for any loss of funds as a result of this occurrence. We cannot mark International orders as a gift in order to bypass or reduce any customs fees. This is an illegal practice and as an established business we will not do this.
TERMS & CONDITIONS
- If you are returning a Free Freight item for a Cash Refund, we will not refund our freight cost, which is a minimum of $10 or what you were charged. Even if you qualified for free freight.
- We will not accept any claim for damage on any Surfboards or Sups after they have been signed for by the customer. Inspect before signing.
- We will not refund on any finance sale this includes AfterPay and Q Card. We will only allow exchange or credit unless there is a mistake at our end in shipping or stock holding.
- Should you select an item that is marked as 'Pre-Order’ and pay using Afterpay a 5% cancellation fee will apply that covers our costs if you cancel this because you did not read it correctly.
- By selecting any item that is marked as 'Pre-Order’ you allow a grace period of 14 days from the original date before we will offer a refund.
- We will not accept returns of any sort from any international order.
- We will cover the cost of return freight from our store to you on one exchange for size. Any further exchange in size will be charged at freight cost + $10 handling fee. We will not offer a refund after an exchange of size has taken place. This Excludes Surf / Sup boards, surf bags and international orders.
- Should there be a miss-pick, the wrong item sent, the item is faulty, or the description/image is significantly wrong we will cover freight costs both ways or provide a refund.
- Any item returned to us without swing tags, with pricing removed, or not 100% as it was shipped out to you will have a restocking fee of 10-30% depending on how that item is returned. This will be at our discretion.
- We will not accept returns for any 'In Warehouse' customer orders. This stock would have been brought in at a significant cost to meet your order.
- We will not be responsible for any change of address that takes place after the order is processed. We will provide you the tracking details to contact the courier and arrange this.
- We will not be responsible for the loss of any parcel where there is a shipping request to leave in a place, doorstep etc. Once the courier says it is delivered any claim for anything missing item will be between yourself and the courier company. We will offer assistance where possible.
- We will not issue any refund in the event of a delayed courier unless we are informed that it must be to you by a certain date and time. We cannot be responsible for lack or planning on your behalf.
- We will provide courier details and tracking information upon sending the order. This is your responsibility to track this and ensure it comes. We are happy to assist but you must email us the order number.
- Any special courier charges such as Saturday delivery or Rural delivery excess will not be refunded under any circumstances.
- Returns will ONLY be accepted via our online portal. Any damage or loss of any returned item is at your risk. We strongly advise having it tracked and signed for.
- Sale or Combo surfboards and sups will incur extra freight charges that match our cost prices for this. We will make contact with you. Items over 7'4 in length can only be sent to local main centre depots. We cannot send these to Rural Delivery addresses. Home addresses will incur a surcharge.
