VENT AXIA SPM 5 STEP AUTO TRANSFORMER SPEED CONTROLLER SINGLE PHASE

The Vent‑Axia SPM series is a range of single‑phase, 5‑step auto‑transformer speed controllers designed for smooth, reliable control of AC fans. These units are widely used in commercial and industrial ventilation systems across the UK, including Belfast, because they provide quiet, hum‑free speed regulation and long‑term durability.