Fifth Wheel Feature: Our fifth wheel coupling in pressed steel design with pivot earnings,manual lubrication,as per DIN74081 and ISO 3842. Reduces friction and uneven wear. Infinite lock adjustment provides improved lock and king pin durability.Grip release handle requires minimum effort to operate and improvev safety. Cast top plate,machined flat,provides stronger load bearing surface, reduce friction and uneven wear. Proven hook and plunger design from existing model safe and reliable locking mechanism. High strength casting steel sustain designed for heavy-duty applications with nice feature and safety usage.