The JANTX1N5420 from Micross is a Space Qualified Diode with Dynamic Resistance 4 to 75 Degree C/W (Thermal), Forward Current 3 to 4.5 A, Forward Voltage 1.1 V, Reverse Current 1 to 20 uA, Reverse Voltage 600 V. Tags: Axial-Lead. More details for JANTX1N5420 can be seen below.