Dave, it's just an trichlor feeder + copper & silver. Essentially, it's a like having Rainbow trichlor feeder + a Nature2 copper cartridge combined into one unit.
Here's the page:
http://www.zodiacpoolsystems.com/pro...-inground.aspx
and the manual
http://www.zodiacpoolsystems.com/pro...ds/SL2750.ashx
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