Polarised clip on flip up sunglasses cut glare from reflective surfaces, such as water and roads, and increase the contrast and sharpness in your vision. With the reduction of glare all objects become more distinct and colours more vibrant. Smoke grey lenses perform best in bright sunny conditions, they're considered neutral because they do not enhance contrast nor distort colours. Brown lenses enhance both contrast and depth perception with minimal colour distortion and give great all-weather performance. Yellow lenses enhance contrast and depth perception by filtering scattered, out-of-focus blue light. They’re especially effective in flat light or overcast conditions helping to increase visibility. Copper driver lenses provide sharper contrast and image definition by blocking blue light and they reduce road glare whilst preserving a natural colour balance for comfortable viewing in the day light. They're designed to highlight the critical driving colours, i.e. red, amber and green.