N-FUSE® Midsole technology joins together foam of two different densities. The top foam is less dense for soft cushioning, while the denser bottom foam provides support and compression set resistance.
Ghillie lacing system provides a custom, supportive fit
AT Tread® all-terrain outsole combines a running and trail lug configuration for on- and off-road use
Synthetic/Mesh upper provides lightweight comfort and support
N-Durance® rubber compound for maximum outsole durability
Rock Stop™2 midsole technology provides full-foot stability and protection from debris
Nolan from SoCal 5/14/2010
I use this shoe primarily for sprinting on grass and light running on pavement. It is a very light shoe with average cushioning. I run on the balls of my feet during sprinting and agility drills during Crossfit type workouts outside. I also use them for walking around on a semi-daily basis. The lacing system is excellent and snug. I would not use this shoe for serious off-road running, but would use it for off-road adventuring.
srfnff 5/1/2010
The 621's are the worst NB shoes I have ever purchased. For the last six years I've owned NB 800 series trail shoes. They have been great. My shoe retailer said they couldn't get 800's so I bought the 621's. I bought them snug fitting and they stretched out, and stretched out and stretched out. So much so, that after three weeks my foot slides around so much the shoes are not wearable. These shoes are made with poor quality materials. The heal on one shoe has developed something that sticks out and rubs against the side of my foot. This should not happen in three weeks worth of wear. I used the shoes once on an easy trail hike where I encountered some light pebbling. The shoes slipped and slided around like I was on marbles. Even the soles don't work! Trail shoes? Durable? I don't think so. The 621's are not even fit for the sidewalk. Caveat emptor.