A steam trap comprises a trap body having an inlet and an outlet each defining inner threads. The trap body further includes a spigot defining external threads. Also provided is a cap defining internal threads for engaging the external threads of the spigot of the trap body. A valve element freely moves inside a trap chamber defined between an inner surface of the cap and the valve seat of the spigot. The cap defines a top surface on which a disc of thermally insulative material is juxtaposed. A cup-shaped cover, which may carry indicia such as manufacturer name and model number, is received over the thermally insulative disc.