1. Built-in load-bearing iron block (only large ball 75 mm model) 2. The function is no longer single, the big ball can be used for tendon massage after exercise 3. Self-lubricating bearings, flexible and durable 4. Thickened foam design, non-slip and sweat-absorbing 5. Unlimited venues, exercise anytime, anywhere 6. Material: PP+PVC+silicone 7. Size: The handle is about 13.5 cm long 8. Weight: 30mm model 270g/1 pair, 75mm model 390g/pair
