Free-motion machine quilting just got easier! Hoop is backed with an exclusive no-slip gripper material so you can move the quilt with the hoop with very little pressure. Two knobs on each no-slip Gripper Hoop give you a secure, safe, and comfortable grasp on your quilt. Knobs may be tightened to move as one with the hoop, or loosened to swivel. Works with table or home machines. Go to YouTube to see some great videos that will show you just how easy these are to use. This is a set of two gripper rings, one 11″ in diameter and one 8″ in diameter.