| More information... A self contained, temperature sensitive thermostatic piston controls the opening of the indoor vent disc. In automatic operation the aperture decreases with declining outdoor temperature and increase with rising outdoor temperature. The unit comes complete with wall tube and outside weather protected wall grille.Ordering is straight-forward: simply check the specification sheet provided to establish which unit is most suited to your requirements.For assistance please call our sales office on 01304 215 575 |