High-Energy-Density Each Synergy Digital Cordless phone battery has the capacity to provide long-lasting, continual use. Boasting a high-energy density and high-power capability at a more constant rate, these batteries are made of Li-Ion to provide long-lasting, reliable power. Long-Lasting Power Using these powerful Synergy Digital Ultra Hi-Capacity Cordless Phone Batteries, you can keep your cordless phone consistently powered for longer periods of time. A Li-Ion battery delivers substantially more current than any other battery in its class, boosting performance when servicing high-drain devices. In addition, each Synergy Digital battery is made with high-quality Japanese cells to ensure long-lasting use, so you never have to worry about draining off the battery the moment you really need it. Long-Term Value with Less Waste These Synergy Digital cordless phone rechargeable ultra-high capacity batteries can be charged over and over thousands of times, so there is less waste. Simply charge your cordless phone with the battery inside – and enjoy ultra-strong power for your device time and time again. Not only do you get more bang for your buck, but Li-Ion is also free of toxic heavy metals. As such, these batteries are recyclable and safer to use. 100% Compatible Synergy Digital Batteries are 100% compatible with the original OEM battery. Its ultra-high-capacity provides longer-lasting use than the original OEM battery. Therefore, you can rest assured that your cordless phone will perform at its highest standard possible.