Eliminates twisting and kinking of wire. Neater, faster professional wiring jobs. Efficient use of time (fast setup, easy to move). Average reliable lifetime of 15+ years. 20 in. diameter shock absorbing wire tray. Wire weight automatically controls free spool. Comes completely assembled. Designed for MC, 14/2, 14/3, 12/2 and 12/3 Twin Sheathed Cable. Capacity 150 lbs. Satisfaction guaranteed or get a full refund.