Whatman filter papers are world-renowned as the standard for laboratory filtration and are associated with quality, reliability, and customer service. With an extensive line of filter papers available, they are the optimum choice for many filtering techniques. Whatman maintains a guaranteed quality, reproducibility, and uniformity for all its filters and tests for basic weight, thickness, air flow and mechanical strength.

High retention of fine particles under demanding conditions. Slow flow rate. Very hard and strong with excellent chemical resistance - Hardened Ashless Quantitative Particle Retention Liquid 2.7µm