Snatch block

[Grant Bowker]

The second photo in post #2 seems to have "TEST 8 TONS" stamped and the first photo in the same group seems to have a broad arrow.
To me the broad arrow suggests British Commonwealth. Tons can be either long (2240 pounds, more commonly used in Britain) or short (2000 pounds, more commonly used in USA). Both are different to metric tonnes 2204 pounds / 1000 kg.

The snatch block is probably not a Holmes part as an item suppled with their wreckers as those all seem to be 4 digit numbers (But no snatch block listed where I'm looking).
I was also thinking a safe working load of 2 tons was rather light for things as heavy as CMPs. Is it possible the snatch block was designed for earlier, lighter equipment? Or just for moving smaller loads?