This is a lightweight LED holder that can be mounted both in the front and in the rear of the ZMR250 frame. It will allow mounting one standard 5 cm led segment to the front and rear of the frame, but will add next to no weight to the quad. Every gram counts on mini quads, so the low weight is a definite advantage. The mounting lugs are 3.1 mm high, which is the same as the height of the carbon arms of my quad. This means that the holder fits between the frame plates without any height modification like adding washers etc. If you want a wider bar that can hold two LED segments (10 cm), you will find it here: http://www.thingiverse.com/thing:741329