Stamped on the component side at the insertion end.
Printed on the solder side along the edge toward the insertion end.
overall: 1/2 in x 5 1/2 in x 4 5/8 in
Standard Modular System (SMS) card of unknown function. There are discrete transistors and other components. There is an opaque cover over the components. There are two of these modules. The model number 5300503 appears twice on each of these modules.