ULTRA Series bandpass filter with a 385.5 nm (± 1.0 nm) center wavelength (CWL), a 28 nm full-width at half-maximum (FWHM), and wide-range OD5/OD6 out-of-band blocking from 325 nm to 700 nm (with additional blocking to 1000 nm). This bandpass filter has exceptionally steep edges and greater than 95% average transmission from 374 nm to 397 nm. It is coated on a 2 mm thick polished Borofloat® substrate and mounted in a standard 25 mm (+0/-0.1 mm) diameter, 3.5 mm (± 0.1 mm) thick anodized aluminum ring. Alluxa ULTRA Series fluorescence filters are designed to optimize fluorescence instrument performance, resulting in bright, high contrast images of target molecules. ULTRA Series filters provide better overall performance than our standard fluorescence filters by using a combination of tight wavelength control, ultra-steep edges, deeper blocking, and the industry's highest transmission levels. All Alluxa optical filters are highly durable and hard-coated using our innovative SIRRUS™ plasma deposition process. Contact us for custom sizing.