All red laser pens are not created equal. Most red laser pointers operate at the cheaper 645-670 nm wavelength. But research shows the most effective wave length is 635 nm (within 3 nm of the theoretical limit for a red laser). This laser pen provides the correct wavelength for maximum brightness and effectiveness.
This is the ULTIMATE in a red laser pointer. This laser pen features an on/off button which allows the pen to stay on without holding the button down!