Likewise, we have used Deep Vent with either Taq or Hot Tub with success in long PCR. You can e-mail me for more details. P. Flick -- Parke K. Flick, Ph.D. ch994 at cleveland.freenet.edu Amersham Life Science, Inc. Cleveland, OH 44128 Phone:216-464-9277;FAX:216-360-0975