I don't know what their origional intended use was. I have seen them used on big trucks with red lenses on the rear of the tractor between the rear wheels on the frame and with amber lenses on the bottom of the front bumper. I have also seen them used on the bottom of mud flaps and the rear of boat trailers with red lenses.
Looks like mounting is at each end. I can't see a screw hole so I guess they had a small bracket at each end that covered the end tabs and had 2 screws each.
I didn't do it, no one saw me do it, you can't prove anything! "Bart Simpson"
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