Duracell Ultra 9V MN1604 PP3 Batteries are Duracell’s most powerful 9V alkaline battery. Providing the most power and longest-life for products that are used on a daily basis, Duracell Ultra 9V 6LR61 batteries are the only battery that offers the Powercheck feature. This allows you to see how much battery power is left.
Duracell designed these 6LR61 batteries with high-drain products in mind. If you use radios, wireless, microphones, or security system transmitters you should power them with Duracell Ultra 9V batteries.