The Primus bottle takes a slightly different approach and provides two closures. one to screw without pushbutton and frills, the tightly holding with safety and as a bonus there is a quick release that so far with me also works very well and does not show any signs of wear. I mostly use the normal screw cap, because the quick release can also clean a lot worse and needs to be taken to deal. In addition, the first-named is really tight and the bottle keeps beverages hot for longer. The bottle is processed top quality finishings, grip and yet light and keeps hot drinks about 12 hours hot as she promises it.
Conclusion: This is the first thermos, I can wholeheartedly recommend, because it offers what their competitors only promise. The five to ten euros extra charge is taken as happy to accept it if the quality is right. The two supplied fasteners are commendable, especially the simple screw.