WWII British Army No. 4 MK II 5 BAYONET, SCABBARD, FROG - eBay (item 310055027158 end time Jun-03-08 18:38:05 PDT)
This WWII British Army bayonet is marked, "No. 4 MK II, 5" on one side a7789" on the other side. I see no maker's mark on the scabbard. I can't read what's stamped on the back of the frog except it starts out with a "2".
An eBay seller sold a bayonet like this and said it was for an Enfield rifle. Another seller said it was for probing mines which explains the somewhat screwdriver shaping on the tip.
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