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Pentek FloPlus-20BB Filter - 20" Big Blue Carbon


Retail: $128.41 /ea
You Save: 24%
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Retail: $128.41
You Save: 24%
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This Pentek FloPlus-20BB Filter is a 20 inch Big Blue Carbon Block water filter for use in many water filter systems, especially whole house filter systems. The Pentek 455906-43 is a Big Blue filter (4 1/2" diameter) that features a much higher flow rate in gallons per minute than standard diameter filters (2 1/2" ). The Pentek FloPlus-20BB is specially made for high flow whole house applications where a low pressure drop is needed. This advanced Pentek filter replacement cartridge is specifically made to reduce the bad taste and odor of chlorine and other chemicals in water. It also removes or reduces sediment, dirt, rust, and other common impurities. This filter also removes 99.95% of cysts such as cryptosporidium and giardia. This Pentek FloPlus-20BB water filter is also known by Pentek part number 455906-43. This filter has been tested and certified by NSF International to NSF / ANSI Standard 53 for the reduction of cysts.

Note: This cartridge should be flushed for about five minutes before using the water in order to remove all carbon fines.


  • Brand: Pentek
  • Model Number: FloPlus-20BB
  • Part Number: 455906-43
  • Replaces Part Number: WFP-20BBa
  • Pack Size: 1
  • Dimensions: 20" length x 4 1/2" diameter
  • Flow Rate: 4-5 GPM depending on specific filter system
  • Filter Life: 6 months or 50,000 gallons depending on usage and water quality
  • Filter Media: Carbon block
  • Initial Pressure Drop: 4 PSID
  • Micron Rating: 0.5 micron
  • Temp. Range: 40 - 180° F
  • Connection: Drop in

Compatible Parts:

The Pentek FloPlus-20BB Filter - 20" Big Blue Carbon is the correct replacement for the following part numbers:

Part Number
American Plumber 555017-51
American Plumber WFP-20BB
American Plumber WFP-20BBA
Pentek 455906-43
No results for {X}

Compatible Models:

The Pentek FloPlus-20BB Filter - 20" Big Blue Carbon is correct replacement for the following model numbers:

BrandModel NumberDescription
American PlumberWFP1.5-20BBA FloPlus SystemWater Filters
PentekFPS-20BBWater Filters
No results for {X}
prop 65 California Residents: Prop 65 Warning


Customer Reviews:

Total Reviews: 1 | Average Rating: 5 / 5.0

John Henry2012-10-31

This filter on a water well system in Texas with hard water just works as defined extremely well. The pressure loss was only two pounds (PSI). Also, the Tech. at FilterFast explained that a UV light may not be necessary and after water tests, she was correct. This makes my third one, changed every six months. Highly recommend.

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