Taco "00" Cartridge Circulators are rugged, versatile, quick and easy to install. With their self-lubricating design and no mechanical seal, they provide unmatched reliability that makes them maintenance free. Every Taco "00" circulator features a field-replaceable cartridge that contains all the moving parts. Replacing the cartridge rebuilds the circulator. Field service could not be faster or simpler to perform. Taco "00" IFC Cartridge Circulators feature an Integral Flow Check (IFC) that eliminates the additional installation costs that go along with separate in-line flow checks, improves system performance and further reduces maintenance.