S-40 (SD) and S-40u (Micro SD) memory cards are equipped with intelligent read disturb management (RDM) alongside an autonomous, performance-neutral background "auto refresh" process. This type of data care management significantly improves data reliability and balances out the increasing limitations of MLC NAND flash during long operation time and extensive use in the field. Data transfer rates reach up to 11 MB/sec for write and up to 24 MB/sec for read operations, putting them into SD3.0 speed class 6. Diagnostic functions offering detailed status information plus standalone data maintenance guarantee data retention for many years, even in especially rough environmental conditions and in extreme temperatures. S-40 SD cards are available up to 32 GB; S-40u Micro SD cards are available from 4 GB up to 16 GB.