Energizer 377 batteries provide reliable, long lasting power for your important devices. Small in size, but big on power, trust these button batteries when you need key fob batteries or calculator batteries. Keep your keyless entry system or health monitor powered with these small batteries, or use them to keep your child's favorite toys and games ready for fun. For best results, store these 1.5V button cell batteries in a cool, dry place until you are ready to use them. Each 377 battery lasts up to five years in storage, so you can keep a stock conveniently on hand and ready when you need it.