Widely application: 3 sizes inflatable air shim bags ideal for leveling furniture, window\/door alignment, great kit for contractor tool. Protetcion Material: Air Wedge with Double side TPU pouring 420D Nylon Material design, rounded corners, stiff durable edges, smooth exterior for easier insertion to resist greater strain with higher abrasion performance. Easy Operation: Wring the valve to Right and squeeze pump to inflate. Fits into tight 3\/32gaps and opens to 2 1\/2 wide, 330lbs load rating for max weight capacity. So Many Uses: Appliances, Beams, Cabinets, Doors, Equipment, Furniture, HVAC, Plumbing, Joists, Countertop, Mantels, Bathroom Fixtures, Curtain Walls, Flanges, Windows, and more Warning: Note: Do Not Over Inflate to avoid any damage to the bag or valve. Note - please avoid sharp objects in direct contact with the air wedge. Maximum thickness is 70mm. If the gap is too wide, It can do nothing. Please leave half of the air wedge outside to make it stable and safe. Dont inflate excessively when operate. After being propped up, let the air out. Then put the triangle block.