I have no idea if these are "street legal", they are boat legal. Put one in a cupholder or holster of some sort.
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As far as "street legal", in Colorado to turn an off-road motorcycle into street legal we would have put on a high/low beam headlight, running light/brake light, license plate and horn. I have done this to a few bikes (last one was about 2 years ago) with no problems. I know this does not address DOT tires or turn signals, but any inspections I had to do with the local law/gov't passed. I wish they would pass that bill and let ATVs run on the streets in CO, under a 50 mph on highways and no interstate. All our quads meet these "street legal" requirements, same as we have done to motorcycles.
"Big Bad Wolf" 2004 Sportsman 700 EFI, Mine
"Lil' Red" 1999 Sportsman 335, The Wife's Ride