Therm 5.5kW [12" x 2"] Universal Flo Thru Incoloy Heater [ACC] (26 1004 7S K) skirtrestoration The L160 fit and snap fit The L160 fit and snap fit design give this assembly practical value because sand filter internals work best when they match the original model relationship closely This union kit creates serviceable transitions from FBT thread to 1 1 2 inch slip pipe these design details help the heater integrate correctly with the surrounding circulation and control components rather than functioning as an isolated replacement part 5kW heating output and 12" heater length should be matched to the original equipment requirements before installation