This is definitely an SMLE magazine (Rifle Number 1 Mark III and III*) magazine.
The double rib on the BACK and the tiny spring are the giveaways on this model. The Number 4 magazine had a single long rib.
What is the Factory marking?
I have seen this type of anticorrosion paint before, but cannot confirm its use for tropical climates.
Anyone familiar with what they were using in New Guinea, Malaya, Viet Nam and Burma?
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