Caleffi Boiler Trim Kit w/ Check & Backflow Valve, 1-1/4" Threaded Air Separator, & 4.4 Gal. Expansion Tank

Description The NA553 Series Boiler Trim Kit has 10 configurations that combine 8 common boiler installation components into one simple package. Kit Includes: 551007A: DISCAL® Air Separator (1-1/4" NPT connection) 573002A: AutoFill/Backflow Combination (1/2" NPT connection) 561402A: Expansion Tank Check Valve (2) Brass Nipples 3" NPT Brass Tee Expansion Tank (4.4 gallon)