With only 2mm thickness and 100 100mm size,No Color Cast and is made with premium Germany Optics glass. Size:100 100mm（3.9" 3.9"）. 1 100 100mm Light Pollution Square Filter. K&F Concept Natural Night Filters made of double side Nano-Coating use waterproof and scratch-resistance technology ,bring the high-quality definition, low-reflection and no Vignetting.
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