Unique Glass Membrane - PHE-14 pH electrode uses a semi-micro cylindrical glass membrane (6mm in diameter), making small-sample pH testing easier than ever, and can be tested in high-temperature samples (up to 212°F). Long-Life Reference System - composed of a glass, AgCl, and a reference silver wire. The top end of the slim glass tube is stuffed with cotton, which prevents the reaction between AgCl and electrolyte when the temperature changes. It improves the stability of the reference electrode and extends the service life of the electrode. The electrode uses a BNC/RCA connector, compatible with all labForce® pH meters. This is a replacement electrode for the TS-SS200 portable pH meter.