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 22393, Roloc Disc 361F, 36 YF-weight, TR, 3 in, Die R300V, 7000045093
Dynabrade 93334 Carbide Burr, 3/8" Dia., SD-3 D/C Burr, Ball, 5/16" Flute L, 1/4" Shank
Dynabrade 51623 .1 hp Straight-Line Extension Pencil Grinder, Central Vacuum, 1/8" Collet
3M 62817, Adhesive Sealant 760 UV, Black, 290 mL Cartridge, 7100139449, 12/Case
3M 45714, Cubitron II Hookit Cloth Disc 947A, 120+ X-weight, 3 in x NH, D/F 3HL, Die 300BE, 7100113113
3M™ 94275, Versaflo™ Gold Coated Tinted Over-Visor with UV/IR Protection M-967N, 70071696879, 1 EA/Case
3M 06840, Booth Coating, 5 gal, 7000120531
Dynabrade 51630 .1 hp Straight-Line Extension Pencil Grinder, Central Vacuum, 1/8" Collet
3M™ 17323, Versaflo™ Respiratory Helmet Assembly M-407, with Premium Visor and Flame Resistant Shroud, 7000002395, 1 EA/Case 
