These are British Mark III Hotchkiss dase fuzes for AP shells. They have the EOC stamp for "Elswick Ordnance Company". Note the overstamp "PLUG". In 1910, the Navy required that all shipping plugs be marked as such due to several accidents. Aparrently the ordnance workers of this time failed to recognize that these were actually live fuzes and not simply shipping plugs. Unfortunately, most ordnance workers are only knowledgeble about what they work with themselves and fail to study history and obsolete items. As EOD we had to be able to know not only why something works, but why it failed to work and to recognize the origin and use of an item by it's characteristics. In otherwords, you may not have seen a particular fuze, but you immediately recognize it's function and country of origin or development. This is actually easier in old ordnance and the distinctions between countries are rather blurred today. I used to work with several QUASAs (Quality Assuance Specialist, Ammunition) They thought they knew everything about ordnance, and they were very knowledgable about what was in service and storage during their lifetimes. However, according to some of them, all 37mm ammunition were anti-aircraft projectiles. Of course, we know that the 37mm projectile dates to the St. Petersburg Declaration of 1868 where the signatories decided to ban any explosive projectile of less than 400 grams (14 ounces) in civilised warfare.