1Made of premium optical glass with multiple coatings, it can filter strong light evenly so to weaken the light without affecting the color. 2Can allow the photographer greater flexibility to change the aperture or exposure time. 3Can be used to prevent strong overexposure even when using a slow shutter speed. 4Easy to use, precision thread mount, suitable for any brand of filter holder with same mount. 5Lightweight and portable, easy to carry and store. Good accessory for photography lovers, especially good for outdoor use.Features: 1. Made of premium optical glass with multiple coatings, it can filter strong light evenly so to weaken the light without affecting the color. 2. Can allow the photographer greater flexibility to change the aperture or exposure time. 3. Can be used to prevent strong overexposure even when using a slow shutter speed. 4. The ND2-400 filter we offer is to indicate the amount of light a ND filter can reduce. 5. Easy to use, precision thread mount, suitable for any brand of filter holder with same mount. 6. Lightweight and portable, easy to carry and store. Good accessory for photography lovers, especially good for outdoor use. Specification: Product Type: ND dimming Frame thickness: 1cm Lens compression spring: screw-in Frame material: aviation aluminum alloy Glass material: imported optical glass Caliber: 46MM/49MM/55MM/62MM/77MM/82MM(optional) Hue: medium gray Package List: 1 * ND2-400 Filter