DataLocker devices wipe or destroy data when reset or initialized, or when the key regeneration routine is initiated. In these cases the drive deletes all encryption keys, making the stored data irretrievable.

According to DoD 5220.22-M directive dated February 28, 2006:

8-301. Clearing and Sanitization.  Instructions on clearing, sanitization, and release of IS media shall be issued by the accrediting CSA.

a. Clearing.  Clearing is the process of eradicating the data on media before reusing the media in an environment that provides an acceptable level of protection for the data that was on the media before clearing. All internal memory, buffer, or other reusable memory shall be cleared to effectively deny access to previously stored information.  

b. Sanitization. Sanitization is the process of removing the data from media before reusing the media in an environment that does not provide an acceptable level of protection for the data that was in the media before sanitizing. IS resources shall be sanitized before they are released from classified information controls or released for use at a lower classification level.

DataLocker products have hardware-based encryption and wipe routines that fully meet the requirements for clearing data. 

NIST Special Publication 800-88  Guidelines for Media Sanitization

There is no certification for SP800-88. It's a vendor affirmation and applies to the organization employing the device rather than the device itself. From a device level, we meet the requirements of SP800-88, because we follow the "Cryptographic Erase" option in accordance with FIPS 140-2. This option ensures all user data is encrypted and the cryptographic key used to encrypt the data is zeroized in accordance with FIPS 140-2 requirements. To view our FIPS-validated certificate please see this resource page: Datalocker FIPS Validations