S7-300 6ES7953-8LL31-0AA0 S7 Micro Memory Card, 2MB S7-300 6ES7953-8LG31-0AA0 S7 Micro Memory Card, 128KB, S7-300 6ES7953-8LF31-0AA0 S7 Micro Memory Card, 64KB S7-300 6ES7953-8LM31-0AA0 S7 Micro Memory Card, 4MB