Replacement Batteries Energizer CR2025 for Cayeye, Sigma, Knog, Planet Bike & Mnay Others. Replacement Batteries Energizer CR2025 for Cayeye, Sigma, Knog, Planet Bike & Mnay Others. Note: Photo shows 5 this is for ONLY 2 Batteries. 3 Volt Lithium - Low Drain Energizer Lithium provide excellent low temperature performance w/ 33% lighter weight than Alkaline. Unit of Sale: 2 Batteries Replasement batteries for Headlights, Tailights & Computers from most all manufacturers.