The Yukon Grizzly Locker is the ultimate in locking differentials for street, off-road, & drag racing. Grizzly Lockers provide 100% power to both tires, while still allowing for disengagement while negotiating turns. The Yukon Grizzly locker uses 8620 internals and a patented design to provide maximum strength and reduce common failures. Assembled in the USA! This unit has been approved for competition in NASCAR National & Touring series. All Grizzly Lockers are backed by the best warranty in the business! Yukon covers the replacement unit and covers any collaterally damaged parts and associated labor, up to $2,000! This locker also fits 9.5" & 10" dropouts.