It is a 20mm x 24mm one side takes off the clutch weight assembly, the other side takes off the clutch itsel,Replace honda special tool: # 07716-0020100, 07vma-mbb0100-101, Removes honda locknut: 90231-0231-028-000, 90231-200-010.
Also fits most of other brands: Roketa, SSR, TaoTao, Supermach, Coolsport, Coolster, Hensim, Jetmoto, Jonway, Kazuma, Kinroad, Lance, NST, Baja, BMS, BMX, so on.
SIZE: Total length: 60mm/2.36"; Small End Inner Diameter: 20mm / 0.79", Outer Diameter: 26mm / 1"; Large End Inner Diameter: 24mm / 0.94", Outer Diameter: 30mm / 1.18.