Therafin’s Permobil Corpus 3G Bayonet Style Bracket is attached to a Therafin half tray that is made out of 3/8" clear polycarbonate. Polycarbonate is virtually unbreakable. Bracket fits the Permobil Corpus HD 3G armpads and mounts under the armpad and provides a bayonet style flip mechanism that allows the tray to by loosening a knob. The HD version of the bracket accomodates pad thicknesses up to 1-3/4". Trimline shape half trays have a straight outer edge that offers support for people with weakness on one side and allows more belly clearance.