Fast,easy,light very durable micro drone.The design grips the motors so don't nee even to glue anything just use a rubber band to hold the board and the battery.

UPDATE:

I have tested with 6 and 7mm motors without problem The boards I tested are the eachine h8 and microwii dsm2 ( eachine one get fully protected as the frame has almost the same shape) The batteries used for testing where 150mah and 260mah bigger batteries will have problem to fit because they will be bigger than the drone itself but can be lifted without problem. Very acrobatic flying due at the small distance between the motors.