Material: 3D breathable mesh and sponge pillow, aluminum alloy strap; light and firm. Other functions: U-type sponge mesh cushion, anti-lateral, can reduce head pressure, more breathable, light, more cooling. Flexibility: can adjust the angle and height of the pillow according to your needs (the high-back wheelchair can only adjust the height of the headrest, and the front and back angles of the head cannot be adjusted); fits the travel chair perfectly. Tips: Press the headrest tube directly, pull the headrest, do not remove the U-shaped and curved base, the wheelchair can be directly folded. Easy to install and use: insert the curved base into the left and right handles of the wheelchair, insert the U-shaped base into the left and right sides of the curved base, and insert the tube of head on the home plate, turn the U-base to adjust the forward and backward position of the head, and after determining the position, lock the knob with the curved base and the U-base knob. Field of Application: The diameter of push tube for wheelchair or commode should be 22.2-24.5mm, and it is better to use round tube. Please make sure the width of the wheelchair push pipe is suitable to install the fixed clamp (about 14 inches). Suitable for 16-20 inch wheelchairs (wheelchairs not included).