ValuSep® Solid Phase Extraction (SPE) filters for EPA Method 1664A are designed to provide high recovery and low blank values in Horizon® SPE-DEX® and SPE manifold EPA Method 1664A applications. Each SPE filter consists of glass fibers which have been chemically modified so they retain the oil and grease analytes from the wastewater sample as it passes through the SPE filter. The retained oil and grease analytes are then extracted off the SPE filter using n-hexane and the final weight of the oil and grease residue is gravimetrically determined per EPA Method 1664A. For fastest processing times, use the 47mm SPE filter for suspected oil and grease concentrations less than or equal to 40mg/L and use the 90/100mm SPE filter for suspected concentrations greater than 40 mg/L.