3 Pcs NMB 3V -5V DC 2 Phase 4 Wire Micro Stepper Motor Dia 15mm Step Angle 18 degrees with Metal Gear PM15S-020-SKH4 Motor: Micro 2 phase 4 wire Stepper motor Voltage: 3V-5V DC , Step angle: 18 degrees Motor size: * 15 MM x 11.3 MM The output shaft length: 6.5 MM (with an aluminum alloy gear: top diameter 4.45MM, modulo 0.25) Weight: 9 g