This is the Great Planes ElectriFly power system brushless motor mount. This attaches to the firewall and the electric motor attaches to this mount.

Features:

• Direct replacement for the Great Planes .20-.48 (3.3-7.9cc) and .40-.70 (6-11cc) glow mounts
• Perfect fit for both 35mm RimFire Out-runner 28mm Ammo In-runner motors
• Universal motor mounting bolt pattern insures an easy fit with many brands of motors
• Lightweight aluminum construction for added durability
• Unlimited adjustability from 2.1-3.1 (56-78mm)
• For medium motors

Includes: 

• One motor support for medium motors and all assembly hardware

• Mounting to the firewall and attaching the motor

• Length: 2.53 (64mm)
• Width: 2.18 (55mm)
• Height: 2.18 (55mm)
• Weight: 2.3oz (81g)
• Mounting hole dimensions: 1.325 x 1.325 (33.65 x 33.65mm)