[RMcNeal]

I opted to go 12" and Curt on mine, since Curt was the only one I could find locally in 12".
The 10" was smaller than the contact width between the flat part of the pin box and the B&W Companion hitch I have. The 12" is about 1/2" wider all the way around, but it has worked fine for over 3 years now.