@Lisponger, the hitch extension is about 12". Works great with the bike rack, even with a 4 bike rack, with 4 DH bikes on it. Not a lot of swaying, but the extension is really over built. The inner sleeve (2" x 1/4") that the number receives, is 12" long, with a a 12" long 2.5" x 1/4" outer sleeve, offset just enough to allow the inner to slide into the bumper, and to receive the bike rack. Both ends are completely welded and then 2 rosette welds on each of the 4 sides. So, it is essentially 1/2" thick.