Using this Bobrick B - 543 toilet paper spare roll dispenser is easy. First, mount it on the wall using the provided mounting plate, and the threaded flange will cover it neatly. Then, insert a standard - sized toilet paper roll with a core diameter between 3/4' (20mm) and 1 - 1/2' (40mm) and a width of 4' (100mm). When it comes to maintenance, keep the dispenser clean by wiping it with a mild cleaner regularly. The set screw in the post is there to prevent vandalism, so make sure it's tightened properly. Also, avoid using abrasive materials that could scratch the satin - finished stainless steel. If you encounter any issues, check the mounting and the set screw for tightness.