See GE timers on following link to identify timer:
Link has instructions plus large image you can see segments lifted up and pushed down
http://waterheatertimer.org/GE-timers-and-manuals.html#GE510NTimer knows when to turn lights on-off because segments are lifted up or pushed down.
Push/lift a few segments.
Turn lamp ON
Plug lamp into timer.
Mover switch to Timer ON
Plug timer into outlet.
Manually rotate dial clockwise to see lights turn on-off.
This will show if segments should be up or down.
Set segments for ON OFF times.
Rotate dial until current time lines up with pointer.
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