From the Manufacturer Arlington FB450-1 Fan and Fixture Mounting Boxes for New Construction, Fits Sloped Ceilings up to 45 Degrees. This unit ships with a ready-to-tighten center screw, installed NM cable connector and two screws for bracket installation (held in place until removed by installer). Arlington fittings are carefully inspected and our manufacturing process is designed to prevent the possibility of a defective product leaving our plant. In the event any of our products are found to be defective, we will replace them with new product free of charge. The time limit for this warranty is one year following the date of sale or one year after the date of installation, whichever is the earlier date. This warranty does not apply when the product is used for any purpose other than the intended use as described in the Arlington literature. This warranty does not apply when the product is used for any installation which would violate the national electrical code or any code which takes precedence in a particular jurisdiction. Labor is not included.