I have a box off morse code key set's circa 1960, they are new and work. They 
take a C or D cell, and you can switch between light, buzzer etc., they have 
two spring clips, to hook two together and communicate back and forth. These 
are  quality boy scout type units, like they don't make any more, they would 
be grate for a code class. Price FREE, must pick up in BPT., CT free to first 
request received.................
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