Are you fed up with your gimbal dancing about when the grass tickles it while on the ground? An extra two inches is all you need. Add a bit of height to your DJI arms, especially designed for the TBS Discovery Pro with gimbal.You need a set per arm, so a quad copter will need 4 sets. Bolt them on to the existing frame using one M5 bolt at top (min 20mm in length) and one M4.5 at the base (min 18mm). Attach from both sides of the base.