QKGEN® SD DNA Polymerase is a novel heat-resistant DNA polymerase with strong Strand Displacement activity. The enzyme has the chain replacement activity and continuous synthesis ability of Phi29 and Bst DNA polymerase, and can withstand high temperature of 90℃. These properties make this enzyme the best for Polymerase Chain Displacement Reaction (PCDR). In addition, the enzyme can be used to construct LAMP, tHDA, RCA and NGS libraries. The enzyme has 5 '-3' polymerase activity and 5 '-3' chain displacement activity, but no 5 '-3' exonuclease activity. The expansion rate is 4kb/min, and the optimal activity is at 68℃. In addition, the enzyme has high tolerance to ethanol, guanidine, heparin, serum and plant polysaccharide polyphenols, and its activity is not disturbed during the reaction.