MATERIAL: We use high quality cell cast acrylic material (Grade A+) which is moisture and heat resistant and suitable to cover air vents, ducts or openings all around your house, apartment or office space. The vent covers are manufactured in the USA using high precision laser cut machine allowing us to cut to any shape or size meeting our customers’ needs.MEASUREMENTS: Please order product by the opening size. Listed product sizes refer to the duct opening measurements, outer dimensions of the cover in most cases are 1" longer in each direction. The thickness of the material is 3/16" (4.5mm). The back of the  grille is flat, which makes it very easy to attach to the wall or ceiling without any scratches or gaps.USE: These vent covers are perfect for walls and ceilings, not for floor use. SABA Home Decor offers a luxurious alternative to unattractive, stamped-metal grilles and air vent covers that have always been a challenge for modern interior designers.INSTALLATION: The installation is very easy and fast. Please visit our instruction page for more details. All you need is All-Purpose 100% heavy duty adhesive silicone, no screws or any other hardware is required. Screw mounted version of the grill is also available*. This product is maintenance free, since no corrosion, rust or mold will be formed on this material. * We recommend to use screws for square grills larger than 14"X14" and rectangular grills larger than 16"x10".