Position-Plus+ Seat Cushion 41 X 41 X 6,3 cm Foam / Gel - EachSeat Cushion Position Plus+ 16 W X 16 L X 2 1 2 D Inch Foam Gel Four separate gel filled chambers guarantee stability Safety strap keeps cushion in place Water based gel relieves pressure and cools the skin to prevent breakdown caused by perspiration Side gel improves lateral stability by controlling left right leaning High density foam adds comfort and prevents bottoming out Low Shear outer cover reduces skin damaging friction Front gel controls