Replacement Part Number 669-18-30. Before Ordering, Please Check For The Details To Make Sure This Part Will Fit. FIT FOR The Drive Belt Used On 4 stroke 49CC 50CC GY6 139QMB 1P39QMB Long case engine Scooter, ATV, Go Kart, Moped (Such As Roketa/ Taotao/ Baja/ Vespa/ Jonway). Value 669 Drive Belt With The Characteristics Of Wear Resistance And Corrosion Resistance, Which Is Very Suitable For You To Replace The Original Belt, And The Price Is Only Part Of The OEM One. High Performance 139QMB Drive Belt Made Of Excellent Quality Rubber Material, The 669 18 30 Belts Sold In Our Shop Are Of The Best Quality In The Whole Network, And Are Not Afraid Of Comparison. 100% Brand New,100% Tested Before Leaving Factory. After-Sales Service All Of The Original MINSTAR Parts Are Backed By 1 Year s Carefree Return, And Lifetime Service Against Manufacture Defect, If Defective During Our Warranty Period, 100% MONEY BACK GUARRANTY!BUY WITH CONFIDENCE! Item Package Quantity:1 Product Details: Colour: Black. Material: Fiber Rubber. ( strong and durable.) Interchangeable part number: 669-18-30 Size Length: 669mm ,Width: 18mm ,Teeth Angel: 30 degree Fitment: 4 stroke 49CC 50CC GY6 139QMB 1P39QMB Long case engine Scooter, ATV, Go Kart, Moped (Such As Roketa/ Taotao/ Baja/ Vespa/ Jonway) Package: 1 pcs drive blet Instruction is not included, professional installation is highly recommended. Please be carefully check the goods appearance, size, shape before ordering. How to Select the correct belt 1. Determine the series type. 2. Measure the Outer Diameter (O.D.) of the driven pulley on the jack shaft. 3. Measure the Center Distance (C.D.), which is the exact distance between the center of the engine crankshaft and the center of the jack shaft, must be precise. 4. Use the two measurements, the driven pulley outer diameter and center distance measurement to determine the correct belt part number from the relevant chart below. Friendly tips Belts are rubber products. As the working time increases, the transmission belts are prone to wear or aging. Therefore, the belt and its accessories should be inspected and replaced within the specified time to prevent the belt from breaking and causing damage to the vehicle transmission components. The transmission work is more precise.