Atomic Hawx Prime 120 S BOA Ski Boots 26/27

The Hawx Prime 120 S BOA sits one step below the top of Atomic's Hawx Prime BOA line — the 'S' performance build, a 100mm medium-volume shell around a 120 flex, closed by a dial on the lower shell where the two lower buckles used to be, with two aluminum buckles still on the cuff. That closure is the whole idea: the BOA cradles the forefoot and instep in one even pull and micro-adjusts on the fly, while the cuff keeps the positive bite of a metal buckle. Before anything else, though, this boot picks a foot.

The Hawx Prime 120 S BOA sits on Atomic's medium 100mm last, between the narrow Ultra and the wide Magna, and a prior-generation bootfitter review of the same platform describes a tall, roomy instep over a snug heel — which is why a medium-width foot with a fuller instep tends to settle in cleanly. Memory Fit heat-molds the shell, and the Mimic Platinum liner is fully heat-moldable, so a fitter has real room to chase out pressure points, but molding refines a fit; it does not rebuild a last. Get the volume right first: a narrow foot swims here and a wide one bulges, and the dial does not fix either — BOA wraps the foot, it does not change the width of the shell.

The 'S' marks what you get inside. Mimic Platinum is the top liner in the Prime line and Power Ankle Lock holds the heel where the softer 110 S and 100 drop to lesser liners, and Power Shift 2.0 sets the forward lean across three positions so a fitter can build the stance. The BOA lower earns its keep on comfort — an even cradle with no buckle pinch across the forefoot, adjustable a click at a time without stopping to re-buckle — and it asks for something back: an independent bootfitter review of this platform found the dial version a little harder to step into than the buckled one.

The Hawx Prime 120 S BOA reads its flex against the body driving it. A flex 120 is stiff relative to weight, and a lighter or less aggressive skier will struggle to bend it forward; that skier is better off dropping to the Prime 110 or 100, not muscling this shell with the dial cranked down. Read the number as a direction, not a grade: a flex index is Atomic's own house scale, and nothing makes a 120 here the same as a 120 somewhere else. This is a boot for an advanced-to-expert skier who already drives the cuff, and for a strong intermediate moving up who will grow into it.

The Hawx Prime 120 S BOA ships on a cantable GripWalk sole certified to ISO 23223, which means it needs a binding certified for GripWalk, or a MultiNorm (MNC) binding that accepts it — a binding built only for the plain alpine ISO 5355 standard will not take it. There is no walk mode and there are no tech inserts, so this is a resort boot rather than a touring one; a skier who wants to skin belongs in the Prime XTD. And whatever it goes into, a certified technician has to confirm the sole against that binding and set and test the release on a machine — that is never something we settle in copy.

Against its closest sibling, the 120 S Dual BOA, the split is only the cuff: the Dual BOA trades the two aluminum cuff buckles for a second dial, comes in a touch lighter (1,936 g against 1,981 g here), and lets you micro-adjust the cuff by dial too. Keep this version for the buckle's positive bite; go Dual BOA for the lighter, dial-everywhere setup. Step up to the 130 S BOA only if you have the weight and the strength to want a firmer cuff. Two honest caveats close it out. Atomic publishes 1,981 g per boot at one reference size and nothing per size — the 24/25 130 S BOA and the traditional-buckle Hawx Prime 120 S are the same platform, not this exact boot. PTO's read: the chassis and the fit are real for the medium-volume skier this is built for, but buy it for the fit and the closure, not for the number on the cuff.