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D-20A Culligan Level 1 Undersink Water Filter Replacement Cartridge

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D-20A Culligan Level 1 Undersink Filter Replacement Cartridge

Save 33% (MSRP: $23.99)

Quick Overview

Fits Culligan US-550, US-600, US-600A, RO-2127, RO-3000, RO-3500, and any brand of water filtration system that uses standard 9 3/4 x 2 1/2 filter cartridges
4 10


Undersink replacement water filter for water filtration systems that use 9 3/4 inch x 2 1/2 inch cartridges. Fits Culligan US-550, US-600 and more.

  • Lasts four times longer than the Culligan D-10
  • Recommended for city and well water supplies
  • Granular activated carbon filter media
  • Genuine OEM Product


Package Qty 1
Used In Brands Culligan
Manufacturer's Id D-20A
UPC 033663005105
Advertised Size (in) 10 x 2-1/2
Actual Size (in) 9 3/4 inches (length) x 2 1/2 inches (outside diameter)
Actual Size (cm) 24.77 x 6.35
Media Granular Activated Carbon
Primary Filter Media Granular Activated Carbon
Filter Life (gallons) 1,000
Filter Life (liters) 3,785.41
Filter Life (months) 12 months
Micron Rating (Nominal) 5
Certifications NSF/ANSI Standard 42


Reduces the following contaminants:


The CULLIGAN-D-20 is comparable with the following part numbers

34375 Flotec T02 OmniFilter GAC1-SS OmniFilter UC2
38509 GE FXUTC OmniFilter OB3 RO-3000
49640 GE GN1S15 OmniFilter OT2 RO-3500
432636 GE GN1S15CBL OmniFilter OT32 Sears 34375
3436517 GE GN1S20C OmniFilter SFM2 SY-2000
4234375 GE GX1S01C OmniFilter SFM3 SY-5167
826-746 GE GX1S04C OmniFilter Super TO2
Ace 49640 GE GX1S15 OmniFilter Total 2 True Value 826-746
American Plumber WCC GE GX1S15C OmniFilter Total Plus US-550
Ametek CTR-210 OmniFilter CBF1 OmniFilter U400 US-560
Ametek Kleen-Plus C-10 OmniFilter CBF20 OmniFilter U450 US-600
Ametek US-560 OmniFilter CBF3 OmniFilter U500 1020696
D-20 OmniFilter Deluxe OmniFilter U600
D-20A OmniFilter GAC1 OmniFilter U700

Replacement for the Following UPC