The JSHD4 Anti-tamper is a safety device from ABB designed to ensure that the JSHD4 three-position device is activated only by a hand. It is commonly used in applications where limited machine movement is required, such as during troubleshooting, test running, or programming in potentially hazardous areas.

This anti-tamper device is compatible with various combinations of the JSHD4 top and bottom parts, except for specific configurations like the JSHD4-1 top part and JSHD4 AK bottom part. It enhances safety by preventing unauthorized or accidental activation.