Duracell Silver Oxide Button Batteries provide reliable long-lasting power for your specialty devices. They have up to a 4-year guarantee in storage so you can be confident these silver oxide button batteries will be ready when you need them. Duracell Silver Oxide Button Batteries are great for devices like glucometers calculators and car remotes. Battery Type: Silver Oxide; Battery Size: 309/393; For Use With: Everyday Electronic Devices; Voltage: 1.5 V. • Silver oxide button batteries provide reliable long lasting power for your medical devices watches toys electronics and more. • Engineered for long lasting performance. • Guaranteed for four years in storage. • Sold as 1 Each.