McKissick Construction Block, Series: 680, 3/4 in, 7/8 in, 1 in, 1-1/8 in Maximum Cable, 45 ton, 20 in Sheave Outside Dia, Bronze Bushing Bearing, Roll Forged Sheave, 2 Grooves, 38.25 in L x 5.84 in W x 4.25 in THK