Power for the Next Generation Alkaline 2200 mAh Rechargeable Door Lock Batteries Synergy Digital is a professional battery manufacturer that has grown to be one of the leading companies for batteries in all kinds of forms, including rechargeable AA, AAA, 9V, 12V, Ni-MH, Ni-CD, Alkaline, and Lithium. We are committed to satisfying every customer through our reliable battery life, improved rechargeability, stability, and guaranteed compatibility. We have gained increasing popularity for our commitment and attention to detail to customer needs. Moreover, Synergy Digital carries an array of hard-to-find batteries so customers can easily and quickly find the right battery they need. Guaranteed Compatibility with Your Original OEM Battery 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 door lock will perform at its highest standard possible. Compatible Replacement Battery for: Saflok X-GAA-FC42 and many more... Ultra Hi-Capacity Battery -- Made of Alkaline Each Synergy Digital Door Lock 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 Alkaline to provide long-lasting, reliable power. Made with High-Quality Japanese Cells to Ensure Long-Lasting Use Using these powerful Synergy Digital Ultra Hi-Capacity Door Lock Batteries, you can keep your door lock consistently powered for longer periods of time. An Alkaline 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. Provides Safe, Ultra-Strong Power for Your Door Lock -- Free of Toxic Heavy Metals These Synergy Digital rechargeable, ultra-high capacity batteries can be charged over and over thousands of times, so there is less waste. Simply charge your door lock 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 Alkaline is also free of toxic heavy metals. As such, these batteries are recyclable and safer to use.