"You get six band sizes for multiple applications, and the pliers can be used parallel or perpendicular to the cylinder block. Works by placing a band around the piston, covering the rings and hooking pliers into the band and squeezing. Product Type Compressor tools, Single, Pair, or Set Set. 2 7/8in. -3 1/8in. 73-79mm 3 1/8in.-3 3/8in. 79-86mm 3 3/8in.-3 5/8in. 86-92mm 3 5/8in.-3 7/8in. 92-98mm 3 7/8in.-4 1/8in. 98-105mm 4 1/8in.- 4 3/8in. 105-111mm"