ALTRA Men's Experience Flow

The AC4® Active Comfort Sock uses two of OS1st’s signature technologies for the ultimate comfort experience. The AC4® is built with nano-bamboo charcoal cushion where it counts and OS1st’s cooling Skin Thin™ Technology for temperature regulation

The Experience Flow (formerly known as the AltraFWD Experience) is all about a ride that’s smooth, effortless, and efficient. Glide through daily workouts, crush long training runs, and smile through miles with the run club crew.