A hot-start version of Takara Ex Taq DNA polymerase, which combines the proven performance of Takara Taq polymerase with the proofreading activity of an efficient 3'-to-5' exonuclease, for high-sensitivity, high-efficiency PCR. Ex Taq is optimized for amplicons up to 20 kb from genomic DNA, and up to 30 kb from lambda DNA. Separate tubes of Mg2+ plus buffer and dNTP mix are supplied with the hot-start polymerase.