Whatman Group manufactures Glass Microfibre Filters with Borosilicate Glass. Whatman Group manufactures English mill making fine, handcrafted paper. The Glass Microfibre Filters with Borosilicate Glass has binder free glass microfiber that is chemically inert and binder glass microfiber. These depth filters combine fast flow rates with high loading capacity and the retention of very fine particle, extending into the sub-micron range. Glass microfiber filters can be used at temperatures up to 500°C and are ideal for use in applications involving air filtration and for gravimetric analysis of volatile materials where ignition is involved.