The Wall Saver™ allows for easier routine maintenance flushing and helps protect floors and walls from leaks. Made of injection molded no-break polypropylene will not rust, corrode or crack. Wall-mounted drain pan fits under most whole house tankless water heaters and is required by building codes. Recyclable and non-toxic. US Patents 8104634 and D653745. Each pan includes a dual-size 1 in /1-1/2 in drain fitting with gasket.