The Tattle™ device uses a paddle mounted to a stainless steel rotating shaft. This shaft passes through an aluminum housing and is sealed with O-rings. The paddle forms a gate through which gas must pass in order to go through the indicator. On the outside, a flag is connected to the shaft and, on rotation of the paddle, is raised to indicate a change in the gate position. This raised flag, visible from a distance, has "tattled" that gas has passed through the device and a release has occurred.
By installing a Tattle™ downstream of all PRVs in the system, the system operator can visually inspect all PRVs without the use of specialized equipment. Because they can be seen from a distance, they can be installed in areas that are difficult to access, thus preventing an unnecessary and difficult in-depth inspection process. This ease of use saves time and effort and can prevent accidents and injuries associated with the inspection process.