3038-POLOLU 30:1 Micro Metal Gearmotor HPCB 12V
This gearmotor is a miniature high-power, 12 V brushed DC motor with long-life carbon brushes and a 29.86:1 metal gearbox. It has a cross section of 10 × 12 mm, and the D-shaped gearbox output shaft is 9 mm long and 3 mm in diameter.
Key specs at 12Â V: 1000Â RPM and 100Â mA with no load, 9Â oz-in (0.6Â kg-cm) and 0.8Â A at stall.