Item No PN-SPMG-819 Description Speed Passion special design 1/8 on road Steel Pinion Gear - 19T. These precision - made gears mesh with Silver Arrow's Series of Brushless Motors and other brushless motors with a 5mm output shaft. this durable motor and pinion gear combination can be used on 1/8 On Road Car, including In addition, the gear size is stamped for easy identification and a 4mm x 4mm set screw is included with each gear.