Used on models w/ square tube front axles. John Deere TRACTOR: 520 (WITH SQUARE TUBE FRONT AXLE) John Deere TRACTOR: 530 (WITH SQUARE TUBE FRONT AXLE) John Deere TRACTOR: 620 (WITH SQUARE TUBE FRONT AXLE) John Deere TRACTOR: 630 (WITH SQUARE TUBE FRONT AXLE) John Deere TRACTOR: 720 (WITH SQUARE TUBE FRONT AXLE) John Deere TRACTOR: 730 (WITH SQUARE TUBE FRONT AXLE)