Blue Yellow 
Blue Lime The Superior 4.5
Altra say: "What do you get when you improve on the already adventurous Superior? A lightweight, lightning-fast shoe you can trust on any trail. This certified speed-seeker is trail-ready with a MaxTrac™ sticky rubber outsole, the lightweight and responsive Quantic™ midsole, and the improved upper that’s more locked-in and durable. Throw in improved breathability, better drainage, and a removable StoneGuard™, and the Superior 4.5 is ready to blaze trail like never before."
In addition, breathability is improved and the decoupled nature of the TrailClaw™, as well as multi-directional, carved lugs for improves traction and reduced weight. To top off this already awesome shoe the StoneGuard™ is completely updated to resemble the skeletal structure of a foot for better performance and dynamic flexibility.
- Stack Height: 21 mm
- Outsole: MaxTrac™ Rubber with TrailClaw™
- Upper: Seamless wrap-around engineered knit
- Insole: 5 mm Contour Footbed with removable StoneGuard™
- FootShape™ Toe Box with Fully Cushioned Zero Drop™ Platform
- Stack Height 21mm
- Midsole: Quantic ™ with InnerFlex™
- Weight: 6.6 oz. / 187 g
QUANTIC
New midsole cushioning with a perfect blend of plush, responsive cushion and a lightweight ride. Grid-like flex grooves in the midsole allow your foot to flex where it needs to for more speed and improved performance
TRAILCLAW™
Conquer the gnarly terrain with our TrailClaw outsole technology. Our trail shoes feature canted lugs positioned beneath the metatarsals to provide traction where your foot needs it most. Each lug is strategically placed to ensure fast uphill climbs, stable descents and superior traction across muddy trails.
ZERO DROP™ PLATFORM
Places your heel and forefoot the same distance from the ground to promote low-impact technique, naturally align body posture and strengthen lower leg muscles weakened from running on elevated heels.
GAITER TRAP
This innovative hook-and-loop tab conveniently secures your trail running gaiters to the shoe without having to strap them below the outsole. This prevents annoying debris from building up beneath the shoe.
STONEGUARD
Sandwiched between the A-Bound and EVA midsoles, StoneGuard offers flexible protection from the rugged terrain by deflecting rocks into the midsole for a smooth, stable ride.
MAXTRAC
This amazing combination of grip, traction and durability will allow you to tackle more terrain, more often. Featured on the new Lone Peak 4.0 Series.
