This is a Trinity Revtech X-Factor 10.5-Turn Spec Class Brushless Motor. The X-Factor spec class brushless motor has a revolutionary timing ring and a locking end plate systems. Only 6 short screws (no long screws) to make it lighter. X-Flow Cooling which pulls more air through the can, reducing motor temperatures. Also made with CNC Machined Aluminum to allow for a more accurate deviation reading.