Abstract: A pulley block or sheave includes a pulley (3), a mounting frame (2) for the pulley and in which the pulley is rotatable, and a ratchet wheel (11) rotatable with the pulley and including ratchet teeth (12). A pawl (15) is carried by the mounting frame and is movable to engage the teeth to prevent or inhibit rotation of the ratchet wheel and the pulley in one sense and disengageable from the teeth to allow free rotation of the pulley. A spring mechanism (13) is included for urging the pawl into engagement with the teeth, the spring mechanism being movable relative to the frame between a position in which the pawl is held away from the teeth by the spring mechanism and a position in which the pawl is urged into engagement with the teeth by the spring mechanism, and an actuating member co-operating with the spring mechanism is provided to move the spring mechanism between said positions.