It offers durability for positive or negative-pressure movement of light particles. It withstands temperatures from -40 to 250°F and is available in one or two-ply versions in diameters of 1 to 24 in. The TD-S/TD-HS is a one or two-ply vinyl laminate polyester hose with an enclosed spring-steel helix for flexibility. It features a wear strip that resists abrasion. It withstands temperatures from -40 to 180°F and is available in diameters of 3 to 12 in.

Hi-Tech Duravent, 300 E. Main St., Georgetown, MA 01833, (978) 722-1255,