The product is a premix system composed of GoldStar Best DNA Polymerase, Mg²⁺, dNTPs, PCR stabilizer and reinforcer, with a concentration of 2×. It has the advantages of simple and rapid operation, high sensitivity, strong specificity, good stability, and can minimize human error and contamination. The GoldStar Best DNA Polymerase included in the product is a chemically modified heat-activated hi-fi Polymerase. The Polymerase has 5 '-3' DNA Polymerase activity, 5 '-3' exonuclease activity and 3 '-5' exonuclease activity. Compared with the GoldStar Taq DNA Polymerase, the Polymerase has higher amplification efficiency and lower mismatch rate under normal PCR conditions. The chemically modified enzyme had no polymerase activity at room temperature and is effective in avoiding the nonspecific amplification caused by the nonspecific binding of primer and template or primer dimer at room temperature. The activation of the enzyme required incubation at 95℃ for 10 min, which could be integrated into the existing PCR thermal cycle program. The optimized buffer system maximizes the effect of the enzyme and achieves high-fidelity, high-specificity, high-amplification and high-sensitivity amplification of the target fragment. This product has been added dye (blue), and can be directly electrophoresis detected after the reaction. Most PCR products obtained by amplification have an "A" base attached to the 3 'end, so they can be directly used for T/A cloning. It is suitable for conventional PCR reaction and high fidelity gene cloning and other experiments.