United Industries who are leaders in air pollution control equipments have extended the techniques of minimizing air leakage to rotary airlock valves also.

This type is suitable for mounting on roofs or in ducts; the casing is made of mild steel having robust construction. The casing has flags at the inlet and outlet for fixing the fan on a duct or wall. In this type the impeller is directly mounted on motor shaft with suitable wall frame and motor support brackets.