This is a standard size/quality piston to suit 10mm piston pin models including:
Yamaha 2 stroke 50cc horizontal Minarelli type engine with 40mm diameter piston:
3KJ, 3YK, 3YJ Jog / Jog Z / Super Z / ZR / EX / ZS etc
Jog Poche, Aprio
Vino (all 2 stroke)
BW'S 50 (Zuma) SA02J 2
Adly 2 stroke 50cc horizontal engine:
Silver Fox 50
other 2 stroke 50cc horizontal. PGO PMX
Polaris 50cc quads with 2 stroke horizontal engine
Chinese made 50cc scooters with 2 stroke horizontal engine.
Includes piston, rings, pin, clips. Sample image shown.