Software card for SINAMICS D4xx
The Siemens 6AU1-400-2PA01-0AA0 is a CompactFlash card preloaded with SINAMICS drive software V2.x and the SIMOTION kernel for SIMOTION D4xx controllers. It's not a generic memory card — the software image is tied to the drive family and kernel version, so swapping it between different controller generations won't work.