When I purchased my Colorado, it had this Curt base plate installed. I removed it and now it's available for free to anybody that can use it. This is used when you want to flat tow your Colorado/Canyon behind an RV. Looking at etrailer the part number seems to be C88FR. It's a long shot, but maybe somebody has a use for it, before I take it to the recycle center? Cost is over $500 new. Nope, I won't ship it, its heavy.