Abstract: A closure is shown for an equipment sub. A closure door is carried by a sub body and movable thereto between open and closed positions for providing access to a pressure vessel. Various improvements are disclosed including a new mechanism for positioning wedge shaped arcuate segments between the door and the sub body, a retainer mechanism for guiding movement of cross bars, a split hinge adjustment mechanism for adjusting planarity and concentricity between the closure door and the sub body, an increased annular wall body thickness region surrounding the sealing surface for reducing warpage during welding, a pressure lock rod member which also engages a combination of cross bars and a crank for driving the cross bars, and a pry bar that can facilitate better manually operated leveraging of the closure door.