Using this soap dispenser is easy. First, make sure you have 4 'D' Cell batteries (not included) and insert them into the dispenser. Then, if you're mounting it on the countertop, note that the maximum thickness it can handle is 2 inches (50mm). If your sink rim is 3/4 inches (19mm) or thicker, use the included spacer. When you place your hand within 4 inches (100mm) of the sensor lens, the dispenser will automatically release a controlled amount of soap (0 - 8ml). For refills, use OneShot® soap. With 800ml of soap, you can get about 1000 hand - washes, and 1600ml will give you around 2000 hand - washes. Keep in mind that this is just the dispenser, so if you want a full starter kit, look for B - 8263.18. To maintain it, regularly clean the chrome spout cover to keep it looking shiny and functioning well. Also, check the batteries periodically and replace them when they're low.