Nokta FoRs Gold, a Gold Cube, 2 Keene Sluices and Lord only knows how many pans....not to mention a load of other gear my wife still doesn't know about!
On the second line, I can make out “4 INCH”, on the fourth line “SWL 1,950LBS” (I think) and on the fifth line the centre word “STRENGTH” followed by some numbers and "LBS."
I suspect this is a Safe Working Load (SWL) tag with weights specified in pounds (LBS). These are normally attached to things like chains, slings, hoists, winches and cranes with the letters SWL followed by a weight indicating the maximum load specified by the manufacturer that the equipment can handle to avoid failures or accidents.
The US stopped using the term in the 1990s, and switched to WLL (Working Load Limit) tags as a result of legal debate about the meaning of the word "safe."
Aluminium didn't see use for 'everyday' items until the 1890s and wasn't in common use until the mid-20th Century. The lettering style on the tag suggests it's 20th Century.