An improved method and equipment for tissue/vessel sealing is disclosed for the sealing, coagulation and transection of tissue during surgical procedures. The improvement is accomplished through better management of heat and moisture present during tissue treatment by having tissue grasping surfaces comprised of an outer non-conducting region and an inner conductive region, and including channels in the jaw assembly to direct steam and moisture away from surrounding tissue. The outer region follows the perimeter each jaw, isolating the treatment zone and preventing steam and excess heat from leaving the tissue treatment zone, reducing thermal margins and unintended patient burns. The outer region also prevents surrounding moisture from affecting the treatment zone and allowing more consistent results.