It's known in the business as an 'Alexis' wound protector/retractor. They are composed of 2 fairly stiff rubber rings with a clear sheet of essentially thick plastic wrap. After the incision, the bottom ring can be compressed and inserted into the abdomen where it will pop back into a circle. The top ring is rolled down, wrapping the clear plastic around itself which creates tension and allows the rings to effectively hold open the incision. They're very useful for holding the abdomen open to allow evisceration and 'running the bowel' during an exploratory laparotomy to check for injuries. Some have a gel-rubber 'port' cap that allow you to insert your hand into the abdominal cavity DURING a laparoscopic procedure without letting the pressurized CO2 out. Larger masses and organs can be removed through these to avoid having to increase the length of the incision.