BrotherHobby Folding 1660-3 are folding 16" three-blade propellers for large long-range and heavy-lift drones. They are designed and intended only for the BrotherHobby Avenger 5215 V5 415Kv motor. They mount on the motor bell via the included 35×6.1 mm adapter and are supplied as a pair in CW and CCW rotation.