Toyota U-Bolt Plate. These are designed for the standard 2.5" Toyota leaf spring from all the Toyota trucks. It will fit an axle from 2.5" to 3.5" in diameter and it will work with a 63" Chevy spring swap. All of our U bolt plates have 3 spring pin location options. They are .375" HR P&O Steel plate and can work with .5625" (9/16) to .625" (5/8) U bolts, we recomend 5/8", why use a lighter piece of steel when you don't have too?