Any water bottle, glass down stem diffuser, slide, small airtight bottle/pill bottle, straw, florescent bulb holder from any hardware store. 1. Burn a hole into the base water bottle and insert down stem 2. Learn how to make a pill bottle percolator (basics -> http://forum.grasscity.com/bongs-bubblers-water-pipes/207839-howto-pill-bottle-percolator.html) 3. Bondo, epoxy, gorilla/hot glue, rubber cement, and/or tape will do to seal it. Wax/putty around the glass stem will help make it air tight Charcoal+ water filters the best