The P-trap assembly on your sink traps waste and prevents sewage gas from escaping. Change a P-trap with the help of this free video presented by a professional and experienced plumber. Expert: Terry Matsamas Contact: www.towersplumbing.com Bio: Terry Matsamas has worked for Towers Murray Plumbing since 1991. Filmmaker: Michael Burton Series Description: Knowing how to perform basic pluming chores can save you hundreds of dollars in home maintenance fees. Learn basic plumbing skills from a professional plumber in this free video series.