This is the 6ES7954-8LE01-0AA0, a spare-part Flash-EPROM memory card for SIMATIC S7-1x00 CPUs and SINAMICS drives. It holds 12 Mbyte of program and data memory on a 3V Flash chip, rated for 500 000 write/delete cycles minimum and 10-year data retention after final programming. The card is physically compact — 24 mm wide, 32 mm tall, and only 2.1 mm deep — so it slides into the CPU slot without adding bulk to the panel layout. At 3 g it's negligible for shipping or handling.
Because it's a mature spare, don't expect it on a shelf. If you're filling a BOM line for a line-down repair or a scheduled PM, send the RFQ — we'll confirm availability and lead time before you commit.
The 12 Mbyte capacity is the key fit parameter — it determines how much program code and data the CPU can load from the card. The 500 000 write/delete cycle endurance matters if you're doing frequent firmware updates or recipe swaps; for a typical machine that gets updated once a year, that's a 500-year service life from the flash alone. The 10-year data retention means once programmed, the card holds its contents through a decade of powered-off storage.