Forged super alloy steel-Quenched and Tempered. It is forged by special alloy steel with high intensity and high toughness, and then it is heat treated .Proof tested and certified. Forged extra wide, Heavy duty retaining collar, with stainless steel locking spring. Unlimited number of assemblies and disassembles. Besides a perfect design the Coupling-link is equipped with a special pin retention system. The pin has a recession in the middle where the locking bush holding a helicoid shaped spring lies. The design of the pin, spring, and bush guarantees safe retention of the locking bush, in case the wire of the spring should break .The performance is increased by 25% compared with G80 products.