We offer two versions of each our TRF89900 dual band TIRF filter sets, each providing greater levels of blocking of the TIRF lasers than our 89900 series filter sets. One version (“-EM”) utilizes additional, single band emission filters which match the quad band emission filter in the filter cube. This option requires an emission filter wheel to house the additional emission filters. The other option relies on one quad band emission filter which provides extra blocking of the TIRF laser, and is housed in the filter cube. The highest signal/noise levels are obtained with the “-EM” versions, however for workers who need very fast switching or who don’t have a filter wheel, the alternate version is an excellent option. The Ultra-Flat Dichroics in our TIRF sets are 2mm thick for distortion-free reflection of TIRF lasers with surface flatness =/> 0.5 waves/inch P-V, RWD. All catalog TIRF sets are mounted in Chroma’s metal TIRF cubes. For more information, please see the supporting materials on our TIRF filter set webpages.