1O-rings play a buffering role in the fishing process and can be flexibly applied. 2Easy to use, it can help you quickly change the sub-line. 3It is often used in fast pins, etc., and can be cushioned by the elasticity of rubber when catching big fish. 4The inside and outside are smooth and exquisite, not hurting the strands, and the elasticity is super strong. 5Made of quality material, safe and durable for long time use.