Glycerin pipes are a type of glass pipe that has an inner chamber filled with glycerin. These freezable hand pipes often feature a coil, as it allows for a longer smoke path which cools the smoke more. Glycerin Pipes can be placed in the freezer, usually for up to 12 hours, which supercools the glycerin. Smoking with this cold glycerin pipe will result in the coolest, smoothest hits you've ever had! Shop the best freezable pipes right here! If you enjoy freezable hand pipes you should also check out our freezable bong section!