CR123 Lithium replacement batteries.

Use these batteries to power select models of the Dakota Alert driveway alarm transmitters. They will last longer than typical alkaline batteries making your driveway alarm work longer and more reliably.
4 Pack CR123 Lithium Battery Advanced construction with Lithium technology Lasts up to 5 times longer than alkaline batteries Used in select models of Dakota Alert transmitters Suitable for all other applications calling for CR123 batteries.

High Performance CR123A 3V Lithium Battery (Quantity: Pack of 2 / EMG), Accessories & Parts, Batteries, Standard Batteries - Airsoft Superstore

UltraTech IM-CR123A - CR123A 3V Lithium Battery, 12-Pack - Alarm Grid

Duracell DURDL123ABPK Duracell High Power Lithium batteries provide reliable, long-lasting power for your specialty devices. They have up to a ten-year guarantee in storage so you can be confident these lithium coin batteries will be ready when you need them. To help ensure the safety of your children, they come in a child-resistant package. Duracell Lithium Coin batteries are great for devices like glucometers, calculators and car remotes.