Stavo Industries, through its ErtelAlsop division, manufactures cellulose-based, depth filter products, including plate and frame filter presses, filter pads, Zeta-Pak lenticular cartridge housings and cartridges. The ErtelAlsop sterilizable Zeta-Pak filter cartridges are available in 10 standard porosities ranging from 0.25 to 15 microns nominal for filtration of products, such as biochemicals, active pharmaceutical ingredients, plasma fractions, vaccines, sera and large volume parenterals. The company serves customers in the chemical, cosmetic, electrical utility, food and beverage and pharmaceutical industries. ErtelAlsop also designs and manufactures custom filtration systems. ErtelAlsop was formed through the merger of Ertel Engineering and Alsop Engineering. Stavo Industries traces its history to 1932 and is based in Kingston, N.Y.