https://www.cisolube.com/products/dual-line-lubrication-system/
CISO autmotic dual-line systems can be used on large systems with dispersed lubrication points that require varying lubrication quantities. These central dual line lubrication systems utilize two main lines that are supplied alternately with lubricant from a high-pressure pump via a change-over valve at up to 400 bar (5 800 psi) Branch lines, along the main lines, are connected with dual-line metering devices to supply a large volume of lubricant to the lubrication points Within large dual-line systems, end-of-line pressure switches are used to control and monitor the centralized dual line lubrication systems.