. FastDigest buffer for 100% activity Low concentration available O buffer for 100% activity Recombinant enzyme R buffer for 100% activity Tango buffer for 100% activity Thermal inactivation at 75°C in 10 min Klenow Fragment is the Large Fragment of DNA Polymerase exhibiting 5'→3' polymerase, 3'→5' exonuclease (proofreading) activities, but lacking 5'→3' exonuclease activity.