The Pentek 255643-43 is the correct replacement for:
The Pentek 255643-43 Inline Filter Cartridge is a 5 micron carbon block filter that helps to reduce chlorine taste and unpleasant odors. Also known as part number 255643-43 and GS-215CB-5-G, this water filter cartridge is tested and certified by NSF International to ANSI/NSF Standard 42 for material requirements only. This Pentek Inline Filter is sold on the web in a case quantity of 12 only.
Pentek Inline Drinking Water Filter specifications:
For optimum performance, replace your Pentek 255643-43 Carbon Block Filter every 6 months, depending on water quality and usage. This John Guest Inline Filter has a 1/4" Quick-Connect port.