Features: Small and light weigh,easy to install and operate. Suit for 1/10 RC brushed/brushless motor car. High quality aluminum 7075,hard anodized on the gear surface,more durable and wear-resistant. 5Pcs set gives you more choice and make your RC car have best performance. A M3 set screw (12.9 level) has been added to each pinion gear. Specifications: Brand: KingVal Teeth: 16T 17T 18T 19T 20T Gear size: 16T ?3.175*?9.54*9mm 17T ?3.175*?10.07*9mm 18T ?3.175*?10.6*9mm 19T ?3.175*?11.13*9mm 20T ?3.175*?11.66*9mm Diametral Pitch: 48DP Suitable shaft diameter: 3.175mm Material: Aluminum 7075 Package List: 1 x 16T Gear 1 x 17T Gear 1 x 18T Gear 1 x 19T Gear 1 x 20T Gear 1 x Screw set