New Energy Micro Lithium Cell 24 Single batteries.
The USPS announced 5.16.12 10 AM EST No international shipments of any lithium batteries are allowed. Please do not order if you are outside the USA.
Dimensions : 24.5 mm diameter x 3.0 mm height 3 volt 290 mAh. Weight 4.6 grams. May be packaged in individual plastic package.
This is from the American Watchmakers-Clockmakers Institute 1998-2000 Edition Handbook on Battery Number System. This Battery is cross-referenced as: AWI L20, Energizer ECR2430, Duracell DL2430, Maxell CR2430, Panasonic CR2430, Renata CR2430, Toshiba CR2430, Varta CR2430, IEC CR2430,CKS1855 Emerson Research.