Use the blue light laser pen to see how Blokz lenses block out harmful high energy visible (HEV) blue light. Click <a href=" /blog/seeing-believing-test-blokz-blue-light-pen/">here</a> to learn how to use the pen and other details. <br><br> <b>Safety Precautions</b><br> Do not aim the laser beam into the eye or look into the aperture of the pointer. Never aim orshine the laser pointer at anyone. Don’t test the laser beam on Blokz lenses while wearing them, as small amounts of blue light may still pass through the lens. Laser radiation is potentially harmful. This is not a toy. Keep out of reach of children.