Well, after I was dome with changing the NRV on some lanterns that unthreaded nicely, I went on with my Primus 535. No luck there, had to drill it out. It all worked fine in the end. So, today, Radius 119, old old lantern. The NRV tool slipped, rounded the head. Not good. Well de-solder pumptube, how hard can it be? Well, easy it turned out. But again the NRV had in this case also to be drilled out in the end. But after resolder, watertest and all, it worked fine.