This is the Motor Mount for the Great Planes ElectriFly RimFire Motors with a can diameter of 50-63mm. FEATURES: Aluminum construction Four point shape INCLUDES: 50-63mm RimFire Motor Mount REQUIRES: Fastening to model and attaching motor SPECS: Length: 3.2" (81.5mm) Width: 3.2" (81.5mm) Thickness .20" (5mm)