This Y-Not Robots 4224 base will mount to existing Tetrix channel hole patterns, and is made to fit the ZTE Speed phone for the upcoming FTC season. Mate with the matching cover (http://www.thingiverse.com/thing:999616) for a secure option of mounting your control device. Cover mounting holes aren't threaded, but are sized pretty close to self-tap using existing Tetrix bolts/screws. Features: • No support needed for printing • Hole pattern matches Tetrix • Incorporated cutouts allow for access of phone functions/charging **Edited for better fit, 10-28-15; alignment/spacer tabs were added to tighten up the phone within the mount.We've played with a few different options, but 25% seems to be the best option for robustness vs print time. Your mileage may vary.