Description Three bolt hole air filter foam insert for 50cc GY6 139QMB engines. Let your 50cc scooter breathe by replacing your dirty air filter foam insert. A clean air filter element helps your scooter or ATV start easier and run smoother.Please check the dimensions on the Specs tab to see if this is the correct air filter foam insert for your Chinese built 50cc GY6 139QMB engine. Specifications Three Bolt HolesOverall Length: 282 mm