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:
Includes: One motor support for medium motors and all assembly hardware
Requires: Mounting to the firewall and attaching the motor
Specs:
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)