Ideal for gravimetric analysis and environmental monitoring. These papers are made of the highest quality alpha cotton cellulose with low ash content. Papers are double acid washed in hydrochloric acid followed by hydrofluoric acid, then rinsed with ultrapure water to neutralize. Sold in packs of 100. Manufactured to exacting standards for uniform performance collect fine precipitates (m) such as Srso4, Baso4, Hgcro4, and colloidal dispersions; gravimetric analysis.