SR54 / 389 silver oxide 1.55V button battery. These High-Grade Silver Oxide "button batteries" are used in many items ranging from watches, calculators to toys and portable hand-held appliances. Size: 11.6 x 3.05mm.
KEEP OUT OF REACH OF CHILDREN
This product poses a serious health hazard if swallowed. If swallowed you must go to emergency immediately.
Swallowing can lead to chemical burns, perforation of soft tissue and death. Severe burns can occur within 2 hours of ingestion. Seek medical attention immediately.