Mounts on the Model JR - 4 Spindle Cable Dolly (as shown) or the Model SR - 8 Spindle Cable Dollly. This accessory facilitates pulling above ceilings, thru bar joist, or into horizontal cable trays. Pulley adjusts fron 8'-11" up to 12'-6" above the floor. *** Must use with DGW-SR or DGW-JR Unit. *****