Prop stopper for RC folding props (Parameterized)

When using a folding propeller with a pusher aircraft, it's critical to have a prop-stopper to prevent the blades from folding back past center when the motor is stopped. If you don't have one, the blades can cross and will then cause an imbalance so bad it will rip the motor off of the plane when you start it back up.

This device solves that problem and also prevents the blades from snapping forward too far on start which can (depending on the aircraft design) cause damage to the plane.