A microSD or microSDHC card is suitable for the Garmin sat nav DriveSmart 66 MT-S.

- Storage capacity: The card can have a capacity of 4 GB to 256 GB, but a 32 GB card is sufficient for your requirements.
- File system: The card must be formatted in the FAT32 file system. If the card is larger than 32 GB, it must be formatted with the device.
- Certification: It is recommended to use a card that is specifically certified for Garmin devices to ensure optimal performance and compatibility.