Tth Polymerase is a thermostable DNA polymerase originally isolated from Thermus thermophilus. It has a 5’-3’ polymerase activity, a 3’-5’ exonuclease activity, and, in the presence of Mn2+, an additional reverse transcriptase activity. It is active at 74°C and can withstand up to 95°C. Thus in addition to amplifying DNA, its thermostable nature also makes it ideal in reverse transcription since higher temperatures can overcome secondary RNA structures. Thus Tth Polymerase is ideal in applications such as PCR, RT-PCR, reverse transcription and cDNA synthesis.