This type is miniature Worm Gear DC Motor, which can change shaft rotation direction while the wiring positive and negative be changed.Its also have addition two characteristics: (1)With self-locking, the output shaft cant rotation when switch off, that is self-locking.( 2 ...This type is miniature Worm Gear DC Motor, which can change shaft rotation direction while the wiring positive and negative be changed.Its also have addition two characteristics: (1)With self-locking, the output shaft cant rotation when switch off, that is self-locking.( 2) Gearbox output shaft and motor shaft are come to be a rectangle, its widely used in various of occasions that require special install size.