The AMP Lock HLP-58-418 is a hitch lock all made of stainless steel to offer a better corrosion resistance. This material absorbs shock also instead of breaking under pressure. It fits on receiver tube with 5/8 diameter and 4-1/8’’ lenght (outside dimension of the receiver). AMP Lock hitch locks are made to resist a lot of attempts as torch cut, liquid nitrogen and its mass of material of 3 pounds combined with its swivel design is slowing down major of cutting attempts. This lock can be keyed alike with all Amplock locks from Ultimate and Standard Plus Series.