Motor diameter: 27.6mm Motor Length: 38mm Output shaft diameter: 2.3mm Output shaft length: 15mm Screw hole diameter: M2.5 Screw hole distance: 16.5mm Weight: 58g Voltage: DC 6.0 V no load current: 1.0A speed: 25500 RPM Voltage: DC 7.4 V no load current: 1.2A speed: 32500 RPM Voltage: DC9.0V no load current: 1.3A speed: 37000 RPM (relatively easy to heat) Tips: The power of these engines is very large. When high current is required, high power lithium battery power supply is usually needed. The higher the power supply of at least 8 A or more, the better.