First put it in a cup of boiling or really hot water for about 30 seconds, bracket and suction cup. Then take them out, but leave one suction cup in. Push it into the hole and keep turning it at the same time. It should go in slowly. Then take the other one out and do the same. The Suction cup attachment is a pain, turning the heater knob is a pain, but it is a very good heater, I recommend it to everyone.