AC535 1.25" BK-7 plain glass filter.
Made in the UK by Astro Engineering this high-quality BK-7 plain glass filter is designed to prevent the ingress of dust and debris when used with modern webcam and CCD imaging cameras.
The filter should be fitted to the nose-piece immediately to stop dust particles entering the camera body and falling on the CCD chip once the lens is removed. Dust motes and the shadows they create - known and dust bunnies - will begin accumulating the moment the chip is exposed by removing the lens.
Supplied in a shock and dust-proof plastic storage case.