RC4WD 540 Crawler 20 Turn Brushed Motor. 

Features:

Custom Made 540 Steel Case

Chrome Plated Case

Build in Capacitor for Minimizing Glitch

High Torque Magnet and Rotor

Small Footprint (50mm long)

Tuned for Rock Climbing and Scale Driving

Polished Bushings

Specifications:

Body OD: 1.39in / 35.5mm

Length: 1.96in / 50mm

Output Shaft Length: 0.43in / 11mm

Output Shaft OD: 0.12in / 3.1mm

Min and Max Voltage Range: 2.4V-30V

Weight: 5.5oz / 156g

(At No Load) RPM @ 7.2V: 20000 +10% , 2Amp Current

(Rated load) RPM @ 7.2V: 18400 +10%, 7.92Amp Current

Designed Operating Temperature Range: -10°C to +60°C

Shaft end play: 0.1mm to 0.5mm

Noise Level: < 78DB