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.

Dynabrade 13016 Arbor Assembly 1/2"-20 Female Thread - 1/2" Male Thread
ACS CX1250 Diamond Belt, 1/2" X 24" 30u
3M™ 07011, Supplied Air Respirator Hose W-9435-50/07011(AAD), 7000005373, 1 EA/Case
Dynabrade 98272 1/2" NPT Female Plug
3M™ 72787, Calibration Kit 529-04-48, Large, 7000052154, 1 EA/Case
3M 77197, Scotch-Brite™ Roloc™ Deburr and Finish PRO Unitized Wheel,TR, 3 in x 1/8 in x NH, 8C CRS+, 7100109130, 40/box
Dynabrade 13509 Dynastraight Finishing Tool, Rear Exhaust, 6,000 RPM, 5/8" (16 mm) or 1" (25 mm) Dia. Arbor
Dynabrade 95842 Dynabrade Air Lube 10W/NR, 1 Pint
3M™ 72013, Adapter 529-04-50, 110-120 VAC, 7000131705, 1 EA/Case 
