Monoflanges are used as an alternative to multi valve systems. These valves are specifically designed to provide a compact installation for gauges or transmitter instruments and can be mounted directly onto a vertical or horizontal flanged connection. With the help of a monoflange, isolation, venting and instrument mounting is possible in a single unit. Monoflange installations help to reduce the weight of the earlier conventional method of installation. As the height of the installation is reduced, the risk of damage at times of vibration is also reduced.