https://www.heat-maker.com/knuckle-info-exchange
Core Exchange Details Cores must be in OEM condition (not modified), free of major damage (rust and/or pitting is ok) and must match the knuckles...
knuckleinfoexchangeheatmaker
https://www.dbmcoils.com/en/heat-exchange-unit-manufacturers/
Since 1981 we design and manufacture heat exchange unit solutions with expertise, innovation and a strong commitment to energy efficiency.
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