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Behind the Design:
ACG Ultrafly

From sketch to screaming fast.

Behind the Design: ACG Ultrafly

Behind the Design: ACG Ultrafly

From sketch to screaming fast.

Behind the Design: ACG Ultrafly
Behind the Design: ACG Ultrafly

We watched the fastest 100-mile runners and the message was loud:
A waterlogged shoe is certain death.
So we tested our mesh for the deluge.
Satisfied only by ruthless drainage; a sieve for the most unrelenting wet you can find.
Holey and light 100 miles later, and more to be had.

We watched the fastest 100-mile runners and the message was loud:
A waterlogged shoe is certain death.
So we tested our mesh for the deluge.
Satisfied only by ruthless drainage; a sieve for the most unrelenting wet you can find.
Holey and light 100 miles later, and more to be had.

Behind the Design: ACG Ultrafly

We watched the fastest 100-mile runners and the message was loud:
A waterlogged shoe is certain death.
So we tested our mesh for the deluge.
Satisfied only by ruthless drainage; a sieve for the most unrelenting wet you can find.
Holey and light 100 miles later, and more to be had.

Behind the Design: ACG Ultrafly

We wrapped the outsole by zone to save weight.
Fortified at the toe but with a naked heel, for flying.

Behind the Design: ACG Ultrafly

Inside, a carbon plate, split to flex over tree roots and rocks who'd like to
see you stumble; built-in adaptation for terrain unknown.

And on the bottom, lines inspired by trailblazing markers say KEEP
GOING THERE'S MORE.

Inside, a carbon plate, split to flex over tree roots and rocks who'd like to
see you stumble; built-in adaptation for terrain unknown.

And on the bottom, lines inspired by trailblazing markers say KEEP
GOING THERE'S MORE.

Behind the Design: ACG Ultrafly
Behind the Design: ACG Ultrafly

The whole thing grounded by a Vibram sole—
Versatile tread for whatever ails you,
Wet sand or pebbles or a downhill zag.

The whole thing grounded by a Vibram sole—
Versatile tread for whatever ails you,
Wet sand or pebbles or a downhill zag.

Behind the Design: ACG Ultrafly
Behind the Design: ACG Ultrafly

Then we put it to the test. Again. And again. So many agains.
Through mud, water, grit and gravel. More miles than sanity.

Until we could say:
It's our most-tested trail product yet.

Neurotically tuned for racing; our answer to the elements.

Behind the Design: ACG Ultrafly
Behind the Design: ACG Ultrafly

Then we put it to the test. Again. And again. So many agains.
Through mud, water, grit and gravel. More miles than sanity.

Until we could say:
It's our most-tested trail product yet.

Neurotically tuned for racing; our answer to the elements.