Union Strata

The Union Strata is a medium to medium stiff flexing freestyle binding, that I chose for park riding, but ended up using everywhere.

I bought the Union Stratas as a second set of bindings, with my main set still being the old Burton Cartel.

Features of the Union Strata Bindings

6/10 Flex

Just a touch above a medium flex

Stage 6 Duraflex ST Baseplate

This is Union’s mid flexing baseplate, which has a lifetime warranty.


Forma Lab Ankle Strap

A thin, but comfy strap.

union strata ankle strap

Strata Duraflex ST Highback

OTE Fused Vaporlite Bushing

TS 2.0 Hexgrip

The strap can be used both over the toes, or around them. The hexagon section is stretchy, and will tightly wrap over the toes of your boots.

hexgrip toe strap

Extruded 3D Aluminum Heelcup

Magnesium Ratchet

Stronger than aluminum, and weighs less.

magnesium ratchet on union strata

Classic FLAD

FLAD stands for Forward Lean ADjustment, and I like the simple screw option for adjustment, rather than fiddly levers like some other models do. Less to break, and something that you probably won’t adjust that often, it is more of a set and forget type of thing.

forward lean adjustment on union strata

Tool-less Strap Adjustment

You can just flip up the little hexagon shapes, which will let you unscrew and adjust the position of the straps, without a need for a screwdrivers. Handy if you have to make a quick change while you are out riding.

union strata ankle strap quick adjust


3 degrees of canting on the footbed, which helps to line your feet and legs in a more natural position.

union strata canting on footbed

Mini Disc

Compatible with 4×2 boards, as well as Burton Channel boards.

union strata mini disc

Sizes Available:

  • Small (6-7.5)
  • Medium (8-10)
  • Large (10.5+)

How The Union Stratas Ride

I originally bought the Union Stratas as a second set of bindings,


The Union Stratas use the Mini Disc, which means that they are compatible with 4×2 pattern boards (all normal ones), as well as boards that use the Channel (Burton, Endeavor, Signal).

You won’t be able to mount these on 4×4 boards, though that is hardly an issue anymore. Only the cheapest or entry level boards are still being made with that insert pattern now, and it is unlikely that you are going to want to put bindings like the Strata on a cheap or very old board.

If you do have an old board with the 4×4 pattern, look at something like the Union Forces with their full size disc, that can mount on them with no problem.

There are an odd couple of boards that have a separate very setback set of inserts just for powder, like the Jones Stratos or Never Summer Peacemaker. It isn’t an issue for riding them like normal, but mini disc bindings won’t work on the very setback stances.

Setting up The Union Strata – and how they ride

One of the most important parts of setting up any bindings is getting the right boot position on the board. Bindings that have a fixed heelcup (Burton, Salomon, Flux etc) adjust the toe and heel position with different settings on the disc.

Brands like Union, Nitro, Ride and a few others make their adjustments in a different way. To adjust the position of the boot in the binding, you slide the heelcup in or out of the binding, so that the toes and heels of your boots have the same amount of overhang over your board.

Both systems work well, though the advantage of the adjustable heelcup bindings means that you are also able to use the disc to make small adjustments to your stance width, that you might be limited with on fixed heelcup bindings.’

If you look closely at the heelcups on Union bindings, you will see a little marking showing the 3 positions that you can set the heelcups to: 2, 1 or 0. Setting 2 is the standard setting, which is what you will need if you have boots on the bigger end of the size range. If you have the smallest boots, you might have to set the heelcup all the way in to position 0.

union strata heelcup adjustment

Setting the heelcup is the first thing that you want to do, because it will affect the position of the straps.

Next I would adjust the ankle strap. The end goal is to have the ratchet about halfway down the ladder when the strap is tight. That will give you the best balance of making the strap easy to get in and out of.

After that I would change the toe cap. On the outside of the binding, there is a forward and back position for the ladder. It will be a little bit of trial and error to see which position works best for your boots.

Forward lean

I like the forward lean adjuster on the Stratas, I am much happier having a very solid locked in system with a screw to adjust the position of the highback, rather than a fiddly and easy to break lever that some bindings have. I would be much more confident I could accidentally smash this on some rocks and not have the whole thing fall apart.

inside of the forward lean adjustment

Ankle and toe straps

Both the ankle and toe straps are very thin and lightweight, and wrap nicely around the Salomon Launch Boa and Vans Infuse boots that I ride with.

Although the toe strap is quite thin and narrow, once tightened over the toes of the boot it has never slipped, it has always been very reliable.

I haven’t noticed any stretching of the straps yet, with about a month of riding on this pair so far.

One small feature that I really liked on the Cartels was the ankle strap that folded our of the way when you were getting in and out of the binding. The straps on the Stratas are quite firm, and they are always trying to stay in their original position, so getting in and out is a little bit more fiddly when you compare the two.

I wondered if the Stratas were going to have enough response for the riding that I am used to, especially seeing that they are a little bit of a step down from other Union bindings that I like, the Force and Atlas.

I rode these bindings for quite a while in powder on the Korua Shapes Transition Finder, then swapped them over to my Ride Zero for park riding.

Overall, they did feel responsive enough for me and any terrain that I found myself on. Toe to heel felt quick and strong, and I didn’t ever feel like I wanted to complain that they were too soft.

Compared to a lot of other bindings that I have ridden on, these did a much better job at smoothing out bumps, and absorbing impacts. It makes sense when you see how much padding is on the bottom of the bindings, and

Boot sizing for the Union Strata

As a general rule, and one that I always follow for my own equipment, is to get the smallest binding that your boot will fit into.

I think that it is a better idea to get the smallest binding (baseplate) that you can, and then just adjust the straps and position to the longer settings. I have found that it is easier this way to get a better or more balanced overall position on the board, so that you can properly center your boots (heel-to-toe).

It works better than getting a larger baseplate, and having to adjust the heelcup in, then shorten the straps and hope you are still centered.

It isn’t such a big deal with Union bindings with their adjustable heelcup. If you are in a crossover size that fits into both medium and large, I would go for the medium.

Their sizing chart doesn’t have any crossovers, so it does make it all a bit simpler.

Size chart


US 5.5 – 7.5

Mondo 23.5 – 25.5


US 8 – 10

Mondo 26 – 28


10.5 – 13

Mondo 28.5 – 31


13 – 15

Mondo 31 – 33

where do the stratas sit in the union line?


  • 5/10 Flex
  • Mini disc
  • $299.99

Less material in the baseplate, but the same thinking as the Strata. Minimal contact to the board, plenty of padding. Slightly softer flex overall, with upgraded straps and ratchets.

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  • 6/10 Flex
  • Mini disc
  • $259.99

Although aimed as a freestyle binding, it still has enough flex and support to handle riding anywhere.

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  • 7/10 Flex
  • Regular disc
  • $279.99

A stiffer flex than the Strata, with the bigger disc and large contact area of the baseplate to the board, the Force has a more direct feel overall.

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Find the best price on the Union Strata

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