This carburetor is the replacement for many Chinese atvs and go-karts of the 139QMB 50cc family. It fits the 50cc 4-stroke models.  

Features:

• Metal Top
• Rubber drain line
• 2-wire male plug
• Electric choke carb
• Air filter mount ID: 34mm
• Intake ID: 18.5mm
• Can be used with a 38mm or 40mm ID air filterd