ProPEX® Lead-free (LF) Male Threaded Adapters connect Uponor PEX tubing to male NPT threads for use in hot and cold domestic potable water systems, residential fire safety and hydronic radiant heating and cooling systems. These adapters are safe for direct burial in soil. Uponor, LF4521313, Male Adapter, 1-1/4 in Nominal, PEX x MNPT End Style, 1-3/4 in Hex, 2.72 in Length, 200 psi Pressure, Brass, 200 deg F, Domestic