The Ooze Glyco Freezable Glycerin Bong is filled internally with liquid glycerin and features a small perc, curved mouthpiece, and includes a matching glycerin-filled 14mm male flower bowl. Most people add ice to water pipes to keep them cool. The Glyco is made of strong borosilicate glass and includes a matching bowl that has a glass screen. Fill the bong to cover the black showerhead percolator. Liquid glycerine becomes very thick when placed in freezing temperatures and stays cold for longer than water. It is recommended to put the Ooze Glyco in a freezer for about an hour before a smoking session.