Single operator constant ground monitor continuously verifying the integrity of the ground system is critical to an effective ESD protection program. The CM400, single wire monitoring products continuously check the total ground loop, including the operator, the wrist band and the coil cord. The systems are compatible with most single wire wrist straps. This is the simplest, and most cost effective way to ensure a wrist strap is continually working. A audible alarm and light will signal a failure.