Amazon's comparison chart shows three sizes for Adidas Team Issue II duffel bags. Small, allegedly, is 24" L x 11.5" W x 12" H. My "one-size" is the Small, but it is about 21" L (measuring end seam to end seam on the bottom) x 10" W x 11" H. Amazon's claim of "one size" confuses the reality that there are three sizes, but all of the purchase documentation just says "one size" and does not cite whether the item is the Small, the Medium, or the Large! (They are viewing these as three separate items, each without different sizes, but they are labeled the same.)
I need to return this 21-incher to get the next larger size, which surely will not be 26" L as advertised but will be long enough for me. I also need to return the one that arrived because Amazon included no shoulder strap in the package, even though the product is listed with one on every relevant page.
Once I receive an appropriate size and a should strap, I think it will be a good bag. BTW, I am using it for guitar accessories, not for the gym.
Lifetime warranty - built to last. Performance technology: hydroshield water-resistant base, as well as ventilated side pocket for dirty shoes and gear. 3 outside zippered pockets and easy access outside mesh pocket to organize your gear. Comfortable shoulder strap pad and super-soft haul handle. Spacious ventilated front zippered pocket and inside zippered valuables pocket for your small items.