Features premium 2-layer design with a dense core and a unique outer layer that comes in different firmness levels. The total diameter is 6" with a 4" high-density core and a 1" outer comfort and firmness layer that wraps around the core. Outer layer is available in 3 levels and is color-coded to indicate firmness. The roller can be used for rehab exercises for upper/lower back, calf, hamstring, gluts and more. It is designed for Pilates, core, abdominal, back stabilization, and strengthening routines. Made in the USA. Rollers are 15” long.