Electrical-electron plug-in unit (NSN 6625-01-438-8393)
Special Features
Hewlett-packard calls this plug-in a fault sense switch; accepts two redundant inputs from independent clocks and connects one to the output port; 1 slot width; visual indicators include led 1/input 1, led 2/input 2, led 3/input 1 selected, led 4/input 2 selected, led 5/output level ok