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.

3M 00570, DynatronAuto Seam Sealer Caulk, 570, White, 12 oz, 7000125070, 12 per case
3M 11414, Roloc Disc 361F, P120 XF-weight, TR, 1 in, Die R100N, 7000045104
3M 26325, PPS Series 2.0 Spray Cup System Kit, Large (28 fl oz, 850
mL), 125 Micron Filter, 7100134637
3M 14316, Marine Adhesive Sealant 4000 UV, Black, 295 mL Cartridge, 7010367955, 12/Case
3M 47181, Polyurethane Adhesive Sealant 550FC Fast Cure, Black, 600 mL Sausage Pack, 7100197989, 12/Case
Dynabrade 51624 .1 hp Straight-Line Pencil Grinder, Central Vacuum, 35,000 RPM, 3mm Collet
3M 88905, PSA Cloth Disc 348D, 40 X-weight, 12 in x NH, Die 1200B, 7010294665
3M™ 07011, Supplied Air Respirator Hose W-9435-50/07011(AAD), 7000005373, 1 EA/Case 
