BHQ™ Probes are oligonucleotides with a Black Hole Quencher™ modification, either internal or at the 3' end. While BHQ Probes are typically 20-30 bases in length, BHQplus™ Probes are typically 15-25 bases in length. BHQplus Probes are an advanced probe type with duplex-stabilising chemistry to allow for the design of shorter oligonucleotides with relatively high melting temperatures. BHQplus Probes are used to detect difficult targets, such as AT-rich regions or SNPs.