This gearmotor consists of a low-power, 12 V brushed DC motor combined with a 4.4:1 metal spur gearbox, and it has an integrated 48 CPR quadrature encoder on the motor shaft, which provides 211.2 counts per revolution of the gearbox’s output shaft.

Motor with 25 mm diameter and 56 mm length, 172:1 metal gear, 6 V operating voltage, 0,55 A to 6,5 A power consumption, 56 RPM speed and 25 maximum torque. Pololu 1577

Miniature high-power motor from the Pololu MP series. 100: 1 gear motor,
the rotation speed of the shaft is 220 rpm, the torque is 1.5 kg * cm (0.15 Nm).
The motor has an extended shaft which makes it easy to attach the encoder. Pololu 2381

Solarbotics GM6 120:1 Mini Gear Motor Offset Output

This gearmotor is a miniature high-power, 12 V brushed DC motor with long-life carbon brushes and a 100.37:1 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. This version also has a 4.5 × 1 mm extended motor shaft.

Key specs at 12 V: 320 RPM and 100 mA with no load, 30 oz-in (2.2 kg-cm) and 0.8 A at stall.

Motor with 25 mm diameter and 58 mm length, 499:1 metal gear, 6 V operating voltage, 0,25 A to 2,4 A power consumption, 11 RPM speed and 30 maximum torque. Pololu 1591

A small, low-power motor with a 5:1 metal gear, 6 V operating voltage, 0.02 A to 0.36 A power consumption, 2500 RPM speed and a maximum torque of 0.05 kg * cm. Pololu 1100

Bipolar stepper motor. It has a resolution of 200 steps/revolution (1.8 ° per step), has a nominal voltage of 7.4 V, and draws a current of 0.28 A per coil. Pololu 1207

75:1 Metal Gearmotor 25Dx54L mm HP with 48 CPR Encoder

Motor with 25 mm diameter and 52 mm length, 47:1 metal gear, 6 V operating voltage, 0,55 A to 6,5 A power consumption, 200 RPM speed and 8,5 maximum torque. Pololu 1574

This gearmotor is a miniature high-power, 6 V brushed DC motor with long-life carbon brushes and a 210.59:1 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. This version also has a 4.5 × 1 mm extended motor shaft.

This gearmotor is a miniature high-power, 6 V brushed DC motor with long-life carbon brushes and a 9.96:1 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.

This gearmotor is a miniature high-power, 6 V brushed DC motor with long-life carbon brushes and a 248.98:1 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. This version also has a 4.5 × 1 mm extended motor shaft.

Motor with 25 mm diameter and 58 mm length, 378:1 metal gear, 12 V operating voltage, 0,1 A to 1,1 A power consumption, 14 RPM speed and 23 maximum torque. Pololu 3258

10:1 Micro Metal Gearmotor

Tamiya 70188 Mini Motor Gearbox (8-Speed) Kit

Motor with 25 mm diameter and 48 mm length, 9,7:1 metal gear, 6 V  operating voltage, 0,55 A to 6,5 A power consumption, 990 RPM speed and 2,8 maximum torque. Pololu 1571

Advanced brushless DC (BLDC) motor controller offering precise motion control with closed-loop FOC. Equipped with an OLED display, 360° slip ring, and RS485 and Grove interfaces, it provides flexibility in integration and mounting, ideal for industrial applications, automation, educational and visual projects. M5stack U182

DC motor with plastic gear 1:48. Equipped with an incremental encoder with Hall sensors.

Solarbotics GMB28 (GM2/GM8 Gear Motor Bracket, Laser-Cut Steel)