Southington, Conn.-based Thomas Products Ltd.’s Model 2100 is constructed with polysulfone (an FDA approved material). It’s an in-line flow switch used for detecting insufficient flow rates in liquids. One feature is the incorporation of a low flow orifice and adapter assembly, which makes the flow switch capable of set points as low as 1 cc/min. in water. Without this assembly, the unit can yield high set points up to 1.5 gpm. This unit can withstand pressure at 250 psig at 70°F and temperatures up to 225°F.