The HR1N5553 from Micross is a Space Qualified Diode with Dynamic Resistance 4 to 47 Degree C/W (Thermal), Forward Current 3 to 5 A, Forward Voltage 1 V, Reverse Current 1 to 60 uA, Reverse Voltage 800 V. Tags: Axial-Lead. More details for HR1N5553 can be seen below.