The ISONE circular fire damper is new generation of totally upgradeable fire dampers. Winner of a gold medal at the "Innovation Competition" during the BATIMAT/Paris trade fair in 1999. It benefits from many advantages: plug-in upgradeable-mechanism option, electromagnetic trigger only for the VCC 24 and 48 and the MICAFLEX hot self-sealing system , Available in 2 versions "low-pressure loss" and "compact", lots of clever points to make installation easy.