✔ Ergonomical U-Shape is designed to safely and comfortably stay in place. ✔ Super fast and easy to take on and off during HIIT interval training. ✔ Allows for a full range of motion to target the under-butt glute muscles. ✔ Can be used as a kettlebell to perform the deadlifts + kettlebell swings. ✔ Includes a FREE super fast and effective 5-minute full glute workout. ✔ 5 LB Weight, durable iron core, no-slip grip, neoprene coating, no-roll design.