These tiny gearmotors are available in a range of gear ratios. All of the micro metal gearmotors have the same physical dimensions, so one version can be easily swapped for another if your design requirements change.
This gearmotor is a miniature (0.94" x 0.39" x 0.47"), high-power brushed DC motor with 100:1 metal gearbox, similar to Sanyo’s popular 12 mm gearmotors. These units have a 0.365"-long, 3 mm-diameter D-shaped output shaft.
The Spektrum AR620 air receiver is a full-range, 6-channel sport receiver with DSMX/DSM2 compatibility and a compact footprint that’s streamlined to fit in a wide range of models. Great for Robots too!