Abstract: A sheave that has the advantage of being able to be quickly coupled to a le, and quickly decoupled from the cable. A further advantage is that the shaft of the pulley on which the cable rides is journaled at each end in side members that interlock when the sheave is in its closed position to support the shaft both from above the pulley, and from below. Other advantages include that the interlock is an arcuate T-shaped extension in the rotatable side member and a corresponding arcuate T-slot groove with which it engages in the stationary side member. The rotatable side member is affixed to the shaft of the pulley and is operable to rotate about the shaft from its closed and interlocked position to its open and disengaged position whereat the pulley is exposed such that the cable, cord or the like may be coupled or decoupled to the pulley.