This is the Hobbywing Quicrun Brushed 550 Motor. These freshly designed motors offer excellent power and control at an affordable price. Using specialized carbon brushes gives these motors an exceptional lifespan and helps to provide great slow speed control. The 5-Slot internal design gives the user great overall power for a nice balance of low speed torque and high RPM performance. Available in several sizes and turns the Hobbywing Quicrun brushed motors are a great choice for your next build. Features: 540 or 555 Can-Size Available Excellent Efficiency Outstanding Response and Control Adjustable Mechanical Motor Timing Modular Design for Easy Service and Cleaning Specifications: Motor Slots: 5 Turns: 13T RPM @7.4V: 14000 Input Voltage: 12.6V Diameter: 36mm Length: 58.5mm Shaft Diameter: 3.175mm (1/8") Shaft Length: 16.5mm Application: 1/10 Crawler, Short course truck, Monster truck Weight: 193g