The US adopted the British Cooper bomb as standard during WWI. The Mark II 25 pound fragmentation bomb was the result. We also adopted the Cooper bomb fuze and designated it the Mark XII nose fuze. We modified the fuze to meet our requirement of being able to drop the bomb unarmed in case of aircraft problems. A small eye screw was attached to the fuze body and a hole drilled in one arming vane. The arming safety wire was passed from the aircraft through these so that the bomb could be dropped with the arming wire still in place. I've attached photos of my Mark II-P version of the bomb. The fuze is complete, but everything is totally inert. It even has the original shipping cover for the fuze. This particular item holds a special place in my collection because an old friend showed up at my door several years ago and gave it to me saying he found it in an old foot locker in his attic. Unfortunately that was all the footlocker had in it, but it was good enough for me.