This is a Quantity of 3 Part # 12121, an Aftermarket Replacement Copperhead Toothed Mulching Lawn Mower Blade by Rotary Corp. With a Cutting Length of 18 1/2", Width of 3", Thickness of 0.1870", and a 5 Point Star Style Center Hole, this blade was designed to be used as an aftermarket replacement for 187254, 187255, 187256, 532187255, 532187256, 594892901, and 532 18 72-55, for use on 54" Cut Mower Decks utilzed on the following models of Lawn and Garden Tractors, and Zero Turn Mowers: GTH26K54T, GTH2654T, LGTH2454, LGT2554, LGT2654, YTH2454, YTH2454T, PBGTGE, PBGT22H54, PBGT26H54, PB22H54, PB24H54, SOGT26H54