Chemistry: Zinc-Air Nominal Voltage: (1.4 ext{ V}) to (1.45 ext{ V}) Typical Capacity: Generally rated between (160 ext{ mAh}) and (185 ext{ mAh}) Diameter: (7.8 ext{ mm}) to (7.9 ext{ mm}) Height: (3.35 ext{ mm}) to (3.6 ext{ mm}) Weight: Approximately (0.5 ext{ g}) to (0.58 ext{ g}) per cell Mercury Content: (0%) Mercury (Mercury-Free) The Duracell Hearing Aid Size 312 (also known as Activair 312 or PR41) is a high-performance zinc-air battery identified by its brown color code. It is designed for consistent power delivery in both analog and digital hearing aids, including those with wireless streaming capabilities.