This 2cm wide heavy duty woven strap with large Round-ring can secure the molded cup with non-slip sole directly to almost any chair leg. It's adjustable from 16inch to 28inch, which can accommodate most players. It will protect your floor from scratches and make sure your cello doesn't slip during a practice or performance. High quality for durable and long-lasting use. Adjustable from 40cm to 70cm to accommodate most players. Folds compactly for storage. Hold cello/double bass stably. Help prevent cello from slipping or damaging the floor. Size: Approx. 30 x 5 x 0.5cm/ 12 x 2 x 0.2 inch (L x W x H). colour: black Material: Plastic+nylon Package Contents: 4 x Cello Antiskid Device Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.