Item Type: C3530 Brushless Motor_x000D_Main Material: Aluminum Alloy, Copper_x000D_Product Color: Black Red_x000D_Weight: Approx. 123g / 4. 3oz_x000D_Shaft Length: Approx. 19. 5mm / 0. 77in_x000D_Shaft Diameter: Approx. 4mm / 0. 16in_x000D_Interface: Approx. 4mm / Golden Head Male 1Waterproof Design: The motor adopts waterproof design and related waterproof processes, which have certain anti corrosion functions and can operate normally in rain. 2High Torque Motor And Copper Wire Coil: Design of a 14 stage 12 slot high torque motor. High purity copper wire coil, maximum efficiency, temperature resistance of 180?200 C. 3Imported Ultra Thin Silicon Steel Sheet: Excellent performance, high magnetic conductivity, high silicon content, good insulation and heat resistance. 4Sealed Bearing: High speed ABEC5 ultra durable imported sealed bearing, with low friction, low noise, high accuracy, and long lasting use. 5Good Workmanship: Exquisite workmanship, beautiful appearance design, small portable size, providing you great using experience.