Skil Care™ Double Bolster Roll Control System, Foam, 34 in. L x 8 in. W x 7 in. H, Blue, 1 Pair Splinting Pans has a chimney valve vent 14283 has a chimney valve vent and is made of PVC Universally sized to fit most manufacturers knee scooters * Effective practical and convenient * An amazing mobility solution that allows the knee scooter user to conveniently and comfortably take their belongings with them and access them easily * Two large pockets with hook and loop closures hold all your belongings including larger items such as laptops purses books etc Wedge design fills gap between mattress and side rail to eliminate entrapment not a restraint for most residents