Used by police officers and professional race car drivers, this wonderful product helps eliminate blind spots ensuring safe lane changes and adding backing up visibility. Standard car mirrors-even with 2 outside mirrors, still have blind spots. The AllView mirror improves that. Don't confuse the Allview with lower price knock off's--your safety is too important.The Allview is anti-glare, shatterproof and vibration free. It clamps on to your existing mirror easily-with no tools.