One of the main criteria in selecting the proper heavy duty connector is the locking system. There are several locking mechanisms available, depending on requirements. The standard single locking system has a lever on the front or side of the housing. Rotation of the lever causes the housing and the hood to be locked together. Double locking systems have two levers that can be mounted either on the housing (standard locking system) or on the hood (reverse locking system) and provide additional security.Now we supply the lever which is made by stainless steel covered by plastic, and did some change.The advantage of those adjustments are anti-corrosion, anti-break, anti-rust and the design is much more ergonomic.