The key specifications of the Activated Alumina Balls 5-8 mm are — Partical Form: Spherical Beads; Surface area: 300-350m2/gm; Pore volume: 0.3-0.4cc/gm; Bulk Density g/ltr.: 800-900. These specifications are based on the standard GEM Equipments design; always verify against your machine's requirement before use. GEM Equipments Pvt. Ltd., established in 1984 and ISO 9001:2015 certified, is one of India's leading manufacturers of compressed air dryers, cooling towers, industrial chillers, and compressed air treatment accessories, based in Coimbatore, Tamil Nadu.