Reduces formicary corrosion;Slant coil for M2430, M3036 and M3642;Internally mounted TXV easily accessible, uses chatleff thread connections;Standard Unico System “latch” method;High efficiency heat transfer surface;Two bi-metal switches to prevent freezing;Stainless steel drain pan;Four row deep refrigerant coil for cooling only, six rows deep for heat pump, allows for greater temperature drop over the coil;Heat pump coil has a 24v relay switch that bypasses anti-frost mode during the heating cycle