This is a two channel process control interface moudule for field installation in the MKS Granville Phillips 350 Controller with 1 line digital display, it has two set point relays for ion gauge. The process control module provides the controller with single-pole, double-throw relays that may be controlled either by 2 digital setpoints or by the built-in manual override switches. See Chapter 4, Page 41 of .pdf manual for instructions on use of the Process Control Module. This is the Process Control Interface Card Module ONLY, MKS Granville Phillips 350 Controller, Cables and Accessories sold separately on this website. The MKS Granville Phillips 350 Vacuum Gauge Controller Instruction Manual can be downloaded below at DOWNLOADS: