I saw this item today and think it’s an Optimus 300. What year should it be from and how can you see. How much could it be worth? Regards Stig
1930s. Somewhat similar to the early (pre WWII) Petromax 826s. Can't tell you exactly the year of manufacture whether its early, mid or late 30s. Optimus did not stamp the dates on their lanterns. Perhaps you check the other smaller features, like the shape or appearance of the filler cap, pricker control knob, pump, etc. Later ones are different.
Welcome, @Stig32 The site policy is to not give valuations, but all your other questions can be resolved. Cheers Tony
If all parts are original, then it would be from the middle of the 30s, so definitely on par with your MC. It wouldn't happen to be a Nimbus by any chance? It looks to be complete (even though someone has removed the nickel), but it definitely needs a service. You are welcome to send me a pm. I'm fluent in Danish.
At least the Optimus is still holding pressure. I've got an early Petromax 828A, 300HK, E&G-made. Its having a bigger problem. I don't know how on Earth did the fount's bottom plate ended up like this:-