This part allows you to mount your TS353 Tx to the side of your Phantom 2. Simply thread a zip-tie through the holes in the Tx housing and then through the air vents (you will need to remove the battery to do this) and tighten! Make sure that the bulky part of the zip-tie is between the back of the Tx housing and air vent (see pictures). I designed the housing and my father coded it with OpenSCAD.
Source: TS353 Transmitter (Tx) Housing / Mount / Attachment for Phantom 2 by jack40k