DW Drum Workshop Heavy Duty Throne with Motorcycle Seat Top Oversized tractor seat top. The 9120 Throne features DW's newly designed double-locking clamp, vise lock seat clamp and an oversized 1-1/4" base for added stability. Oversized tractor seat top Newly designed double-locking clamp Vise lock seat clamp Oversized 1-1/4" base