Alpha Laboratories Grade 601 Qualitative Filter Paper is suitable for numerous applications in pharmaceutical, biotechnology, hospital and environmental testing laboratories as well as for general laboratory use. The filter paper is supplied as 55mm diameter discs with a weight of 73g/m² and a thickness of 0.16mm. It is ideal for analytical applications which require particle retention in the range 5um to 13um. This filter paper has a medium filtration velocity of 88 seconds and a burst strength of 1.95kg/cm². The Grade 601 Qualitative Filter Paper is a direct equivalent to popular brands (Whatman No.1 and Schleicher & Schuell No.595) and is supplied plain or pre-folded in packs of 100.