Hitch Doktor (BLUE), is the Ultimate Trailer Hitch "Shin" Protector. Made of long lasting durable Vinyl Coated Foam Rubber. UV Resistant. Slips over most Trailer Hitch Ball and Nuts. Trailer Hitch "Shin" Protector. Everyone has hit their shin on a trailer hitch at one time or another. The "Hitch Doktor" protects you from hurting you shin when you hit the trailer hitch.  Made of long lasting durable Vinyl Coated Foam Rubber.  UV Resistant  Slips over most Trailer Hitch Ball and Nut.  No need to remove it.  Nothing to keep track of when pulling a trailer.