Since I recently purchased a 2016 GMC Sierra Rocky Ridge, I just purchased a trailer hitch and have been really worried about someone taking it.  Since it is a 4 way ball, they are not cheap to replace.  I have had one already stolen off another truck I had.  This was a purchase that I made at a discounted price for my honest and unbiased opinion.  This is perfect, it fit like it was made for my trucks hitch.  Very easy to install, simply unlock slide in and lock and your all set.  This comes with two different sizes and two keys.  Very well made, and it will stop someone for stealing my new hitch.  The two sizes are 1/2 an 5/8.  The 5/8 worked great slide right into my hitch.  I tested the lock it is very secure, and will protect my slide in.  This is something everyone needs if they have a hitch.  I also have no affiliation with this company.  I would be pleased to recommend this to my followers, friends, and family. 

http://www.amazon.com/dp/B01I193USA

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