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Pentek GAC-20BB Drinking Water Filters (20-inch x 4.5-inch)

Price $63.99 List Price Price $91.41 Save 29%
Availability: BackOrder
Fits most standard housings built for 20-inch x 4.5-inch filter cartridges
Choose a quantity
  • 1Filter$63.99 
  • 3Filters Price $60.21 each
  • 6Filters Price $57.59 each
  • High quality, great value replacement filter
  • Provides better tasting water in every glass
  • Has a long filter life of 6 months or 25,000 gallons
  • Compatible with a wide range of filters and housings
See more product details

Pentek GAC-20BB Filter Advantages

The Pentek GAC-20BB water filter reduces chlorine taste and odor in your drinking water. The Pentek GAC-20BB filter cartridge has a 20 micron postfilter that reduces carbon fines from the drinking water. This filter produces healthier, better-tasting drinking water. The Pentek GAC-20BB filter cartridge is effective at reducing bad taste & odor as well as chlorine taste & odor. The Pentek GAC-20BB water filters are designed to allow maximum contact between the water and carbon, ensuring maximum adsorption. The Pentek GAC-20BB filters effectively provide good general purpose drinking water filtration.

Compatibility and Functionality

The Pentek GAC-20BB water filter is the same as the Everpure EV910842, Everpure DEV910842, Everpure 9108-42, Everpure CGT-204, Bunn C-30, Selecto 101-300, and ShurFlo 15-053-02 Water Filters. The Pentek GAC-20BB filter is NOT recommended for use in a whole house application. This item may not be suitable for providing water to the whole house since there will be a drop in pressure from the carbon media of the filter. If you are looking for a whole house filter, the RFC-20BB filter is a better filter for a whole house application.

Pentek GAC-20BB Filter Design

The Pentek GAC-20BB filter cartridge construction allows water to enter at one end and pass through the entire length of the carbon bed before exiting the other end of the cartridge, an internal expansion pad minimizes channeling or bypass. Before the water exits the cartridge, a 20 micron postfilter helps reduce carbon fines and other suspended particles from the filtered water. The postfilter is permanently fastened to an innovative support basket ensuring that it is firmly secured and eliminating any potential for bypass.

For more information please visit our specifications page and read the Pentek GAC-20BB User Guide

Package Qty1
Used In BrandsPentek
Manufacturer's IdGAC20-BB
Advertised Size (in)20 x 4-1/2
Actual Size (in)20 inches (length) x 4 1/2 inches (outside diameter)
Actual Size (cm)50.8 x 11.43
MediaGranular Activated Carbon
Primary Filter MediaGranular Activated Carbon
Post Filter MediaSpun Polypropylene
Materials of ConstructionEnd Caps: Polystyrene, Outer Casing: Polystyrene, Expansion Pad: Polypropylene, Gaskets: Buna-N (top) and Santoprene (bottom)
Filter Life (gallons)25,000
Filter Life (liters)94,635.25
Filter Life (months)6 months
Micron Rating (Nominal)20
Operating Temperature (°F)40 - 125
Operating Temperature (°C)4.4 - 51.7
Flow Rate (gpm)4.00
Flow Rate (lpm)15.14
ColorBlue / White
CertificationsNSF/ANSI Standard 42
IncludesOne Pentek GAC-20BB 20 x 4.5 Inch Drinking Water Filter
Primary Filter MediaGranular Activated Carbon

Reduced Contaminants

The PENTEK-GAC20-BB reduces the following contaminants:

  • Bad Taste and Odor
  • Chlorine Taste & Odor
  • Sediment

The PENTEK-GAC20-BB is comparable with the following part numbers


User Guide


  1. Turn off water supply. Press red pressure-relief button (if present).
  2. Unscrew housing. Remove large o-ring, wipe clean and set aside.
  3. Discard used filter cartridge. Wash housing with dish soap and warm water using a nonabrasive sponge or cloth. Rinse thoroughly.
  4. Fill 1/3 with water. Add about 1 tablespoon of bleach and scrub to disinfect. Rinse thoroughly.
  5. Lubricate o-ring with clean silicone grease. Change o-ring if any damage cuts or degradation are present. Insert o-ring in groove.
  6. NOTE: This step is important to ensure a proper housing seal. Make certain the o-ring is seated level in the groove.
  7. Insert new filter cartridge.
  8. Screw housing onto the cap and hand-tighten. Do not over tighten. Make sure cap standpipe slips into cartridge.
  9. Turn on water supply. Press pressure-relief button (if present). Check for leaks before leaving installation.