The RNAscope® 2.5 High Definition(HD)- RED Assay, is based on ACD"s patented signal amplification and background suppression technology. The 2.5 HD version is a high sensitive RNA ISH technique and can be used for low expressing gene targets. The RNAscope® 2.5 HD Reagent Kit-RED assay includes the Fast Red dye offers a higher contrast and is the first choice in situ hybridization applications where chromogenic staining with DAB is less desirable, such as staining of highly pigmented lung, liver, retina and melanoma tissue specimens. Also for genes where a lower expression is assumed ACD recommends this assay as the red dots clearly distinguish against the hematoxylin staining and are visible under are standard brightfield microscope.Each kit contains three sub-kits: RNAscope® 2.5 HD Detection Kit (RED) (Cat# 322360), RNAscope® 2.5 Pretreat Reagents-H202 and Protease Plus (Cat#322330), RNAscope® Target Retrieval (Cat#322000), RNAscope® Wash Buffer (Cat#310091).Disclaimer: Photos for 2.5 products will be updated shortly.