DOT RATED BRASS TUBE TO PIPE UNION STRAIGHT. All Male Pipe threads have an application of LOCTITE 516 DRI Pre-Applied Sealant which is a high viscosity, non-toxic, thixotropic, pre-applied, water-based thread sealant for automatic dispensing applications.  It has a “constant on” torque. Operating temperature range: -54° C to 150°C (-65°F to 300°F).