The NEW Trerice Hydro-Therm is the ideal instrument for both hot and chilled water hydronic applications. The blue, organic ''spirit'' fill is easily read without the the environmental concerns of mercury. The sturdy Valox case is available in rigid straight or rigid 90 deg angle configurations. The 2 in stem makes this the perfect instrument for smaller pipeline and other such applications. The 1/2 NPT brass thermowell is included.