The gps attaches to a carbon backing plate via industral velcro. Plate attaches to boom via bolt and it can swivel left/right. Plate has a short extension arm pointing forward torward mast. This tiller has a small limiter line to limit max pivoting angle. Tiller also has a bungie that attaches to the mast rotator arm (down at base of mast on my Tornado). As mast rotates, the bungie pulls the tiller to follow it...which pivots the display the opposite direction. Thus the display always faces the windward aft corner, giving the helmsman a perfect view. Works wonderfully and has stood up well in many regattas now. I'm running the Nauteek 2000 SC which has a big display and be easily be read while on the trap at the rear corner.