a-squared Emergency USB Stick is a portable antivirus for cleaning up your PC. No installation is required, it can be run from a flash disk or USB stick. To clean up your PC, you only have to plug it to your machine, to launch the executable file and the program perform a thorough scan to find any infection. Since it works as an antivirus, you can put a malicious application in quarantine, keep or delete it. It is freeware developed by "Emsi SoftwareGmbH".