Applicable: used for modification, remote control boat, nest ship, pull net boat, remote control submarine, miniature underwater robot. The underwater thruster with unique design provides smooth operation and strong power. The underwater thruster is high performance ensures better work efficiency. With fine workmanship, it has compact structure , eco-friendly and durable for long term use. It can be used for modification, remote control boat, nest ship, pull net boat, remote control submarine, miniature underwater robot. Specifications: Hull length: 50mm Diameter: 31mm Total length: 76mm Propeller: 39mm Operating Voltage: 3V-12V Best state: 6V-9V 7.4V Maximum no-load speed:16800 RPM/min Color: Blue Material: metal Package Contents: 1 x forward motor 1 x Reverse motor Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.