Ronstan Medium jammer, black suits 3-12mm (1/8-1/2 Design, Materials Selection and Advanced Manufacturing Methods combines to deliver Superior Strength and Holding Power, Light Weight and Corrosion Resistance. Cam Profile and Multi-Coil Spring Minimized Line Entry and Release effort. Carbon Fiber Composite Cam Material Provides Maximum Resistance To Heat and Abrasion. Unique Self-Cleaning, SELF-LUBRICATING SLOTTED BEARINGS ENTURE consist High Performance Even when Subject to High Static Loads.