This listing is for 2 filters. AF Series cartridges are double-open end cartridges that fit standard residential and industrial housings. Cartridges are available in 2-1/2" and 4-1/2" diameters and 5", 10" and 20" lengths.  ModelDimensionsAmount of KDFFlow Rate (GPM)Capacity (gal)OperatingMaximumAF-10-201010" × 2-1/2"0.5 lbs.1.01.58,000AF-10-201110" × 2-1/2"1.0 lbs.1.01.515,000AF-20-201220" × 2-1/2"2.0 lbs.1.02.022,000AF-10-2012-BB10" × 4-1/2"2.0 lbs.2.04.035,000AF-20-2015-BB20" × 4-1/2"5.0 lbs.3.05.095,000ProductTypeIonic FormApprox. Ship Wt (lbs)Screen SizeWater RetnetionTotal Exchange CapacityMax. Operating Temp. (°F)AGC-40 (Std, A, AD, AW)Granular Activated CarbonNaDry-28Wet-38+12 -40 Dry Wet 30-40Mine 900Iodine No.250General-purpose coal-based granular activated carbon. Standard grade for low pressure and minimum fines. Available as dry or premoistened (dust free) and as standard or acid washed.ProductTypeIonic FormApprox. Ship Wt (lbs)Screen SizeWater RetnetionTotal Exchange CapacityMax. Operating Temp. (°F)AGC-50 (Std, A, AD, AW)Granular Activated CarbonNaDry-28Wet-38+20 -50 Dry Wet 30-40Mine 950Iodine No.250General-purpose coal-based granular activated carbon. Standard grade for low pressure and minimum fines. Available as dry or premoistened (dust free) and as standard or acid washed.