Two types of alarms – one audible and one visual – alert user to either a low battery or low flow, such a when a particle filter is fully loaded. LED lights on the battery indicate its charge status on and off the charger.
The 3M Versaflo TR-307N+ PAPR assembly includes a TR-302N+ PAPR unit, TR-371+ filter cover, TR-327 easy clean belt, TR-332 battery, TR-341N battery charger kit, TR-3712N HE filter and a TR-3600 Pre-Filter.

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