SPIN cables allow your tips to swivel freely! They are made of a pliable, clear nylon. Lifeline holes can be found at each end of these cables. Insert the T-shaped tightening key into the lifeline hole to assist with securing your tip/cable connection. TWIST tips will work with SPIN cables. For sizes US 2 to US 8 work with size small, US 9 to US15 work with large.