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: 28T 29T 30T 31T 32T Height: 9mm Gear size: 28T ?3.175*?15.9*9mm 29T ?3.175*?16.43*9mm 30T ?3.175*?16.96*9mm 31T ?3.175*?17.49*9mm 32T ?3.175*?18.02*9mm Diametral Pitch: 48DP Suitable shaft diameter: 3.175mm Material: Aluminum 7075 Package List: 1 x 28T Gear 1 x 29T Gear 1 x 30T Gear 1 x 31T Gear 1 x 32T Gear 1 x Screw set