Means it went to England.
Calibre is .38, case length is .767 inch, and British proof test pressures are given in long tons per square inch.
It is probably a Victory Model or an earlier Lend-Lease revolver from WW II. The British went to .38 S&W to replace the .455 Webley about 1928. The official issue was an Enfield top-break revolver that looks a lot like a Webley, but they needed all the guns they could get when WW II broke out and they used large numbers of real Webleys and Smith & Wessons. Smith & Wesson owed them a lot of money after the failure of the S&W Light Rifle project anyhow, and convinced them to take guns instead of cash.
If it is in good unaltered un-refinished condition it is worth a bit of money. Thousands of these guns were rechambered to shoot .38 Special after a fashion so they would sell better as surplus back in the U.S., and many were sawn off to fake snubbys. The ones that remain are of collector interest. If not messed with.