Fanuc A98L-0031-0005 Battery. This can be a Panasonic LR20 in a 1.5V D cell size or LR20-D Alkaline Battery. DNC does carry these batteries , but our advice would be buy them from your local Battery source, etc. Normally four of these batteries are used to backup the system memory for Fanuc 10, 11 and also absolute feedback APC circuit. This Battery has an alternate catalog number in the Fanuc maint manuals of A06B-6050-K061.