Black Rear Fork (Swing Arm) Assembly 

Rear fork body/aluminum forging/welding
Matte silver finished rear fork, matching 121000.01045521 frame
Hexagon flange locking nut/M12 * 1.25/blue white zinc
Chain buffer rubber sleeve/TPU/black
Spacer (rear fork)/φ12*φ22*φ40*10
Oil seal/ φ 20* φ 32*5
Thrust cylindrical roller bearing/ φ 17* φ 30*4
Spacer sleeve (rear fork bearing)/ φ 12* φ 17*35/GCr15
NK17/20 needle roller bearing/ φ 17* φ 25*20
Spacer sleeve (in the rear fork shaft)/ φ 12.5* φ 18* φ 85.5/Blue White Zinc