A surgical instrument for performing a circular anastomosis is disclosed. The instrument is provided with three seals to permit use during endoscopic procedures. The first seal is configured and dimensioned to at least partially contact an outer portion of a compression member and an inner portion of an outer tube. The second seal is disposed about the compression member and is located proximal of the first seal. The third seal disposed about an elongate member, is located proximal of the second seal and is fabricated from polyethylene foam.