Only the "F" had a hinged door in upper body.
The H has a solid globe holder without glass in the bottom of it and lights that hang over the side for the indicators. The J has glass in the globe holder with a light in it that lights up the globe and cylinder. The H has a dump valve and handle in the casting under the cylinder that allows you to empty the cylinder back in the under ground tank. The J has a pipe in the lower casting that you put the nozzle in to drain the cylinder. Therefore the lower casting on the H doesn't have return pipe and the J does.
None have a "Hinged Top", but do have a 2 piece coupling on conduit just above the Bonnet.
