Spindle Assembly / MTD 918-04197BPack Size:1MTD 618-04197, MTD 918-04197, MTD 918-04197A, MTD 918-04197BRotary 12883, Oregon 82-051MTD 700 Series, ZT-17 and ZT-42 No threads in housing, use self-tapping screws, OD of Pulley: 5 1/2 ", Pulley included, Specially designed: to replace 6 pt. star center hole, Height: 6 "