American Water Solutions filter set which is compatible to the following Apec Reverse Osmosis Systems "ROES-50, ROES-75, RO-45, RO-90, RO-PH90, RO-PERM, RO-PUMP, RO-Hi, WFS-1000, ROES-UV75, ROES-PH75, ROES-PHUV75, ROES-UV75-SS includes 1 sediment filter and 2 carbon block filters." 1st Stage: 5 Micron Poly Spun Sediment filter which has great sediment removal capabilities. Dimension 2.5” diameter, 9.84” length” 2nd & 3rd Stage: 5 Micron Coconut shell carbon block which has great chlorine & chloramine removal capabilities. Dimension 2.75” diameter, 9.84” length Activated carbon block filter made with 100% high quality coconut shell carbon. Removes sediment, chlorine, chloramines, taste, odor Our filter set is compatible to work in any standard 10" housing canister, and is recommended to be changed once every 6-12 months.