Spare bongs parts consist of glass on glass bowls, glass adapters, chillums and precoolers. Glass on glass bowls are typically made of pyrex glass. They feature a handle for easy handling. Glass bowls are artistically fabricated and usually have various embellishments. You may spot glass bowls modeled after a skull or even an animal. Chillums and Precoolers enhance the filtration and cooling of the smoke and keeps ash/resin from ending up in the bong water.