Fox Racing

Union BOA Mountain Bike Shoe

What Our Gearhead® Experts Are Saying:

"Compared to other trail shoes in this category, the Union BOA stands out for the combination of the dual BOA Li2 system and the Ultratac outsole with D3O. Most shoes at this price point give you one or the other — either a dialed closure system or a performance outsole. The Fox Racing Union BOA brings both, and the D3O insert in the outsole adds impact absorption that most competitors don't address at all. The molded toe cap and welded upper construction give it durability that holds up over a full season of hard riding."

Trail and enduro shoes earn their reputation through repetition — hard days on technical terrain that expose every weakness in fit, grip, and construction. The Fox Racing Union BOA is built to come out ahead of that process, combining a dual BOA Li2 closure system with an Ultratac rubber outsole and integrated D3O insert that addresses grip, durability, and impact absorption in a single platform most competitors don't match.

The dual BOA Li2 system creates two independent tension zones across the forefoot and midfoot, delivering the kind of adjustable precision that single-dial systems can't replicate. Combined with the stiff internal midsole plate, power transfer to the pedal is efficient and consistent without creating the rigidity that makes shoes uncomfortable during the inevitable hike-a-bike sections of a serious enduro stage. The welded TPU and ripstop upper construction resists the abrasion that trail riding delivers regularly, and the molded toe cap handles rock strikes that would compromise a standard upper over time.

The Ultratac rubber outsole is the performance differentiator for flat pedal riders — grip that holds through wet and loose conditions where most outsoles begin to slip. The D3O insert adds compliance and impact absorption underfoot without softening the platform where power transfer matters. Two-bolt cleat compatibility makes the Union BOA a viable option for clipless riders across all major pedal systems, broadening the shoe's reach across the trail riding market.