Need help with helmets

[MG42]

I am a novice collector who just picks up bits and bobs when I see them but there are a few pieces with which I need a few questions answering.
First is a 1954 (unsure whether this is the correct date) US helmet.

The mark that I think is a date stamp (?) showing crossed swords with 54 opposite

Unsure what this one is

stamp reading 33

Next a typical British brodie helmet (correct me if I'm wrong)

Unsure about the marking that reads KBI (possible maker mark) and a date of 1931. It also reads above J.S.S in similar writing and a 31 underlined and scrached into metal

[Adrian Stevenson]

The first helmet is a Czech M53. Not US.

You are correct on the British helmet.

Cheers, Ade.

[MG42]

Thanks, do you know what the other markings mean and am I correct on date?

[Adrian Stevenson]

Please see here:

Google Translate

[tinlid]

The British MkII was made by Joseph Sankey & sons ( J.S.S) the KB is the steel batch number & it's dated 1939. A nice army MkII.
Aaron

[MG42]

Thanks for the quick reply's and info.
Here's another one which I have no idea about;

The markings on the last photo read AMC 1941, anyone have any idea what AMC is and is 1941 the date on issue/manufacture.

[Adrian Stevenson]

Search "Zuckerman". Lots of info on the forum about these.

Cheers, Ade.

[Nitram]

The Czech vz53 has a leather chinstrap, these were replaced with nylon by the 70's I think. Shell was made in the Czech Republic probably, as it has the Czech army seal of approval (The crossed swords). I'm not sure what the numbers mean, haven't been able to find that out yet.

Nitram

[MG42]

Thanks, the last one of the lot and possibly the latest is this police helmet I picked up at a car boot sale

[Adrian Stevenson]

British MKIV.

Cheers, Ade.