I had the idea to make this model after seeing the extremely popular Pull Copter Finger Ringby agepbiz, sadly I soon realized it contained 5 parts and needed screws so I set to work redesigning the pull copter and optimizing all aspects of it, here are some of the many features: 

• 3 parts: This is the minimum possible parts, this makes the assembly super easy
• Helical gearing:Helical gears are smoother, quieter and cause less vibration
• Wider propellers:This provides more lift for only a tiny bit of weight
• No supports: Super easy print requiring no 3d printing expertise.
• Longer key: More power and rotation speed
• Tighter ring: Fits smaller fingers while still fitting larger ones

Assembly:

Simply place the propeller in the hole and insert the key through the hole. (NOTE:The key only goes through the whole that will make the propeller spin clockwise, so if it doesn't fit try the other side)

ENJOY:)