The new Hobbyking X550 frame is a high quality folding-arm quadcopter frame that offers great looks and performance. Built from light weight yet rigid glass fiber and aluminum, the X550 offers a great combination of weight savings and strength.
This quad features folding arms which make it easy to transport and store. The arms are also two different colors for orientation, silver and red, so its easy to keep your quad flying in the right direction.
All necessary hardware is included, just add your own electronics.
Motor Bolt Holes: 19mm width
More information here: http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=24151