This document provides information on two products: an NR180 Tankless Water Heater that is natural gas, has a 98% thermal efficiency and 15,000-150,000 BTU/hr range, uses 3" PVC venting, and comes with a 15 year heat exchanger and 5 year parts warranty. It also lists an F100F2002 16x25 Media Air Cleaner for $53.95.