The FS4-3SJ Flow Switch by McDonnell Miller is a precision instrument designed for monitoring fluid flow in various systems. This model features a 1 BSTP connection, ensuring compatibility with standard piping systems. Constructed from durable materials, it is built to withstand harsh environments while maintaining accuracy. The flow switch is ideal for HVAC and industrial applications, providing reliable performance and compliance with industry standards. Its compact design allows for easy installation and integration into existing setups.