Smle grenade cup- markings survey

[lithgow1918]

S&B MM on the base and a 6 or 9 is the only mark on the cup of mine.

Any chance it's ".W.W" not "MM" I have seen some marked
"H.W.W
& Co Ltd"
In addition to being marked "S&B"
I am beggining to suspect S&B might not necessarily be a manufacturer mark, as I have seen it along side a number of other possible manufacturer marks to include HL, M&C, H.W.W & Co ltd. I am curious what others think though.