The Air Filter is a direct replacement with those who use an afterrmarket intake sytem. The filter will improve overall air filtration, horse power, torque and gas mileage over stock filters. It is washable and will last the lifetime of your engine. Help to draw more air into your engine so as to improve throttle response and enhance horsepower The fine mesh increases the amount of air flow, straightens the flow and stops sucking hot air from high temperature engine compartment Product description Stainless steel lens 39mm air filter filter for 50cc 110cc 125cc 150cc 200cc gy6 moped scooter atv dirt bike torcycle. Inside diameter : 1.54″ (39 mm) Overall height: 3.15″(80mm) Outside diameter at widest point: 3″(74mm) outside diameter at top: 2″(50mm) Package includes: 1 x 39mm Air Filte