Fit Cuffs – Complete Hard Case. Fit Cuffs is state-of-the-art Training System exclusively developed for Blood Flow Restriction (BFR) Training & Exercise. Fit Cuffs works by inflating solid yet pliable cuffs by means of a solid pressure gauge and sturdy metal quick-disconnectors. (2 x Leg Cuffs V2.1 45-85 cm / 17.7-33.5 Inch + 2 x Arm Cuffs V2.1 20-45 cm / 7.9-18 Inch). One-Size-Fits-All.