Lightweight and compact Proflow SC’s ergonomic design incorporates a curved backplate, which ensures user comfort for long periods of use. Electronic control of the air supply maintains the comfortable airflow, automatically compensating for changes in filter resistance. On board data logging records usage to provide reliable and downloadable maintenance information. Unique 3 year/1800 hour blower warranty, whichever comes first (battery warranty 1 year). Comprehensive alarm system ensures operational safety. Continuous visible monitor of battery status and filter blockage with audible warning of need to recharge/replace the filters. Typical 7-15 hours use from a single charge (depending on the filter/facepiece combination).