Abstract: A sealed housing for a transponder unit (10) in a utility meter pit enclosure has a tube (28), approximately 33/4 inches long and 11/2 inches in diameter, in which transponder electronics carried by a circuit board and an antenna are inserted from the bottom and fitted into guide structures (42, 47) and then a body of epoxy sealant (50) is used to seal and form a recessed lower end of the tube (28) which, in use, may be immersed in water within a subsurface pit enclosure (11). The tube (28) is attached to a cap (22) and suspended through a hole (29) in the pit lid (15). A clamping member (38) is threaded onto the lower end of the tube (28) for trapping a portion of the pit lid (15) between said clamping member (38) and the cap (22). A method of assembling and sealing the unit (10) is also disclosed.