The KOBOLD KSK plastic flowmeters/ flow switches operate on the basis of the well known variable area principle. The medium flows upward through a conically widening plastic measuring tube. The float is lifted by the flowing medium and indicates the instantaneous flow rate on the scale attached to the flowmeter. The KSK series is all plastic with bodies made of nylon Polysulfone or PVDF to handle aggressive media. For the control of flow setpoints, a bistable switch can be provided for the instrument. Reed contacts or transistor switches are available and can be used to monitor and alarm on an upset flow condition. The transistor switch has an LED on the contact housing to indicate switching status.