HOYA 67mm Variable Neutral Density Filter for 67mm ND3-ND400. Hoya 67mm Variable Density NDx3-NDx400 Filter. Hoya 67mm Variable Density x3-400 Filter. Manufacturer: Hoya. The 0.45 to 2.7 density creates a darkening of the entire image, allowing you to photograph with a wider aperture or slower shutter speed than would normally be required.
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