This is an inflatable chest burster from AvP. A burst of air would inflate the balloon like chestburster, and there is a tube under for "blood" to spray out of. Great for when a chestburster needed to BURST out of a chest of someone who was walking or standing in a way where the full burst rig wasnt a viable option.
Photos are from propstore.com, but item is in my collection. They had better photos than I took!
