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K&F Variable Neutral Density Filter K&F X Fader 40.5 mm ND2–ND400 Gray (Model SB7789)
Summary description:
Variable neutral density (ND) filter by K&F, model SB7789, with a 40.5 mm thread and adjustable density range from ND2 to ND400. Designed to reduce light entering the lens for longer exposures, motion blur, and wider aperture control in bright conditions. Gray glass provides neutral color balance. Compatible with lenses using 40.5 mm filter threads.