Hoya Neutral Density ND4 HMC filter 

• High quality neutral density filter
• ND4 filter - 2 stop light reduction
• Hoya HMC coating
• Doesn't affect white balance

Neutral density filters are designed to reduce the amount of light entering your camera lens and should not have any other effect on the image. Reducing the amount of light allows for the use of wider apertures or slower shutter speeds for creative and dramatic effect in bright lighting conditions.