The vibrating rod for sediment level detection is designed to measure the level of solid material that has settled in a tank containing liquids. It is used to detect when a layer of solid material reaches a specific level in a tank. It vibrates in water and then stops vibrating when the solid material reaches the level of the probe. When wired to a horn or alarm panel, personnel are alerted when the sediment has reached the probe and the sediment needs to be removed from the tank. The VR-21 SED is the standard model with a 7.37" insertion length and is recommended for use on the tank wall. The VR-41 SED is a rigid, extended model for top mounting applications and is custom made with extensions from 13" to 13' long.