Your SPT GPS is not a USB memory stick. To get GPS files from the device, and to erase the device you will need to install Bridge on your computer.
Important information:This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions:
(1) This device may not cause harmful interference, and
(2) this device must accept any interference received, including interference that may cause undesired operation.
Warning: Modifications to this unit, not expressly approved by the party responsible for compliance, could void the user's authority to operate the equipment.