Whatman Hardened Ashless Grades (Ash 0.006%) have extremely low ash levels and feature high wet strength and chemical resistance. Diameters listed below are the most popular. Sizes up to 60 cm are available. Please contact your Daigger representative for ordering information. Type Grade 541: Fast filtration of coarse particles and gelatinous precipitates in acid/alkali solution during gravimetric analysis. Typical applications include fiber in foodstuffs, gelatin in milk and cream, chloride in cement and chloride and phosphorous in coal and coke.