These 16mm. Circular S-Power Speed Slings with interchangeable wishbone in 2mm. Dyneema were designed for spear gun shafts with specially polished notches or pins. Using durable, high quality latex, the S-Power with a conical ring prevents the parachute effect and increases the performance of the slings. Offered in a variety of lengths.Materials: LatexDiameter: 19mm.Warranty: Two year limited