title_body: Trying to find a resealable bottle cap
upvoted_answer: Found what I was looking for: WESTMARK 3 Flaschenverschlüsse, Flaschenstöpsel mit Hebel und Gummidichtung, 40 x 60 x 15 mm, farblich sortiert. 
  
   
  
  Now I only need to order a box of these.