Abstract: Apparatus for inspecting containers has a support arm for supporting and transporting the containers. The support arm has a pair of movable arms defining a gap and having a recess for engaging the exterior of the finish or neck of the containers. A light source directs lights onto the movable arms and a detector receives light passing through the gap between the movable arms. The detector emits a responsive electrical signal to a processor which determines whether the container has a bulge and whether it is a reject. The movable arms are so structured and positioned as to enlarge the gap when a bulge is present on the exterior of the finish or neck of the container. One or more support arms are preferably disposed within a container forming machine which forms blow molded resinous plastic containers. An associated method is disclosed.