The most reasonably priced component used on the Cbr125rw 2009 (9) England / Wh Gasket Kit B is the Washer,6mm.
In this schematic the "Washer,sealing 6" is used most often.
The Cbr125rw 2009 (9) England / Wh Gasket Kit B consists of twelve pieces with the Gasket Sheet Kit, (nas) being the most expensive.