Flash Furniture Mobile Ergonomic Kneeling Posture Chair with Back in Black Fabric Ergonomic Design Black Fabric Upholstery Back Height Adjustment Depth Adjustable Back Padded Seat, Back and Knee Rest Knee Rest Pads: 18.75''W x 10.75''D x 2.5'' Thick Height Adjustable Frame Black Powder Coated Steel Frame Dual Wheel Casters CA117 Fire Retardant Foam