The apparatus has a delivery shaft 30 bearing a tubular device constrained within a moveable sheath 36, and a handle comprising a hollow shaft 124 with a static grip 126 and a grip slider 122 movable proximally or distally. The grip slider is connected to a slider block 24 fixed to a sheath hub 6 to which the sheath is fastened. A retraction wheel 120 has a spool 2 for winding a retraction wire 121 connected to a retraction block 20 in contact with the slider block enabling the slider block to be pushed as the retraction block is retracted distally. Initial incremental movement of the retraction block by winding of the retraction wire, moves the slider block and retraction block simultaneously. Subsequently the slider block is movable independently of the retraction block using the grip slider, leaving the retraction block behind.
