Tiffen 55mm Neutral Density 0.6 Filter

Neutral Density Filters
These filters reduce the amount of light passing through the camera lens without changing the color of the scene. They are especially useful in bright light conditions to help prevent overexposure. Neutral Density filters also allow proper exposure at a wider lens opening for reduced depth-of-field to highlight a key subject by making the foreground and/or background out of focus.