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Provides simple, fast, economical method of pH measurement. Sharp color change for each 0.5 pH unit. Can be used with handy dispenser (Product No. 2611000). Convenient for sample pH adjustments. Recom

Pall GN-4 Metricel membrane filters are made of mixed cellulose esters. Non-sterile, 0.8µm Disc Filters are suitable for air monitoring applications and meets NIOSH requirements for airborne metals an

QL Filters are recommended for use in various environmental and wet chemistry reference methods. Extremely pure cellulose filters of nearly 100% alpha content are specially processed to yield negligib

Xenosep® brand ValuSep™ SPE Filters for EPA Method 1664A are designed to provide high recovery and low blank values in Horizon® SPEDEX® and SPE Manifold applications. Chemically treated with a proprie

QL Filters are recommended for use in various environmental and wet chemistry reference methods. Extremely pure cellulose filters of nearly 100% alpha content are specially processed to yield negligib