1:10 RC Model Car Cooling Fan Aluminum Heat Sink Fit 540 550 Motors 7016 Purple Suitable for 540/550/3650 size motor 4.8-6V cooling fan to protect your motor;cooling fan can power up from the receiver Dimensions of fan: Approx.1.18x1.18x0.39 inch/ 30x30x10mm Dimensions of cooling fin: Approx. 1.18x1.57 inch/ 30 x 40mm Total Height: 1.97 inch / 50mm