Premium Quality Replacement Part. Compatible with Bush Hog Models. Ath600 60″, Ath720 72″. Hde Series Zero Turn Mower 49″ 55″ 61. Rdth 60 Rdth Series. Rdth 72 Rdth Series. 3x Spindle Assembly: 50051388, 88757. 88754, 97658, 88753, 9162000. Length: 191 mm – 7.51 in. Width: 136 mm – 5.35 in. Height: 136 mm – 5.35 in.