The Korda Size 11 PTFE COATED DOUBLE RING SWIVEL has been designed to provide maximum flexibility when using a helicopter set up. The extra ring helps to reduce tangles whilst the PTFE coating ensures a super-smooth improved rotation. The PTFE (Polytetrafluoroethylene) coating is a synthetic polymer which has one of the lowest coefficients of friction of any solid. This makes it the perfect coating for our swivels as it reduces friction between the barrel and swivel eye, allowing them to rotate freely which reduces tangles.