W = 4 A = 5/8 B = 5/8 For Leaf Springs That Use 7/16" Diameter Centerbolts C = 3/4 D = 3/8 BENEFITS AND FEATURES: NO NEED TO DISASSEMBLE YOUR LEAF SPRINGS ALL RISER BLOCKS "SLIP RIGHT IN" !!! GREAT FOR LEVELING VEHICLES THAT LEAN!!! ALL BLOCKS ARE 1" THICK AND "STACKABLE"!!! GREAT FOR RAISING OR LOWERING ANY VEHICLE!!! GREAT PRICING!!!