OptiTaq PCR Master Mix (2x) is a ready-to-use solution containing OptiTaq DNA Polymerase, optimized reaction buffer, MgCl2 and dNTPs. Use of OptiTaq PCR Master Mix (2x) allows to save time and reduce contamination risk due to fewer pipetting steps during PCR set-up. OptiTaq DNA Polymerase is a modified and optimized thermostable enzymes blend containing Thermus aquaticus DNA polymerase and Pyrococcus sp. DNA polymerase. The enzymes blend exhibits the 3‘->5‘ proofreading activity, resulting in considerably higher PCR fidelity and processivity than possible with unmodified Taq DNA polymerase. Enables increased amplification product yield in comparison with Taq DNA polymerase over wide range of PCR products. OptiTaq PCR Master Mix (2x) is recommended for use in PCR and primer extension reactions at elevated temperatures to obtain a wide range of DNA products up to 20 kb.