Mush Gemini is made from 50A durometer SBR rubber, with radial flex grooves for a nice moderate grip—trapping tissues deeper than a smooth surface can, but with less intensity than knobbed rollers. Use it to relieve tension in areas that might otherwise be more sensitive to denser tools like lacrosse balls.
It comes in two sizes: Small, 6.8″, and Large, 7.7″.