White Rodgers NAE 4ZAA-18 Thermal Accessories NXT SERIES THERMOSTATIC EXPANSION VALVE WITH ADJUSTABLE SUPERHEAT AND CHECK, EXTERNALLY EQUALIZED, 4 TON CAPACITY, REFRIGERANT CODE Z (R-410A), CHARGE CODE AA (WIDE RANGE), CAP. TUBE 60", 3/8" ODF X 1/2" ODF, BLEED 15%, STRAIGHT THRU BODY