The Paddle Type Flow Switch is installable in tubes 1" and larger without the use of diaphragms, sealing bellows, or O-rings. These units, made of polysulfone, are almost maintenance free. The pressure drop across the instrument is less than 1.45PSI and independent of the pipe diameter. Operation of the unit is clearly visible through the polysulfone housing. They are available with either a normally open or a normally closed contact. Installation is extraordinarily simple. Simply insert the unit in a standard T, or a reducing T, sealed with PTFE tape. Allow for a straight pipe run of at least 3-times the pipe diameter on either side of the T to avoid turbulence.