This probably need be read only by those who own such a pump...
I was inflating my tube the other day, and suddenly the air wooshed out of a leak somewhere. I study the objects in my hands and see that the threaded plastic endcap of the pump, the black dome on the opposite end of the valve head, has exploded. The pressure was too much for it, and it split right open.
I do like this little pump, but it needs a new cap. I have no idea where I would buy just that little part (no, the company website was no help)
Being a Swedish brand, the threads are metric. I was thinking if I could find a brass plumbing cap (it looks alot like a compression fixture) that had matching threads, I could save myself some future failures... but I am on the American west coast, where metric plumbing fixtures are in short supply.
Anyone know of anything that matches those threads?

Wow, not good news since I own one of these too. Did you try emailing Quicker about the broken cap? Most companies who want to stay in business will send a new part for free or at least sell you one. You could try these guys too since they seem to be the only consistent US sellers. https://www.velo-orange.com/quickerpropump.html The threads measure out to 29mm OD or roughly 1.11'' (1 5/32"). If you have any machinist friends who wouldn't charge you $50 to fabricate one that might be your best option since I noticed that the air seal is completely dependent on the recessed 0-ring inside the cap and would be difficult to duplicate with a generic cap. Hmmm, maybe I should donate mine to my creepy neighbor who always want's to borrow my bike tools before it fails on me.