There are many different styles, but essentially an ice catch is part of the water pipe that allows ice to be put in without it hitting your downstream or percs. The pinch style is probably the most popular, where the glassblower puts in a few indentations near the mouthpiece that will hold the ice up. Another style is the doughnut or ring ice catch, which is literally just a doughnut or thick ring-shaped piece of glass that functions the same way. Putting ice in your water pipe really cools off the smoke or vapor!
