Alltrade 648615 Kit 6 Valve Spring Compressor Tool Set For compressing valve springs with the cylinder head removed from engine Powerful lever action tool has handle on the outside Throat depth is9-3/4". Jaws open from 3-1/4" to 8-1/2" to fit large displacement engines Tool set for compressing valve springs with the cylinder head removed from the engine Powerful lever action tool has handle on the outside Throat depth is 9-3/4-Inch Jaws open 3-1/4-Inch to 8-1/2-Inch to fit large displacement engines Kit 6 includes 2-Piece for compressing valve springs