proverbial design of the safety clip

hi

i would like know if anybobody knows about any new significant design improvements (after the perfected Gem type design) with the proverbial design challenge of the paper clip/ or a similar non destructive closure for paper sheets
:bulb:

hi

well in terms of the use of materials there has been different design but all with a cost to it.
if you are lookig for te designs with similar costings the last desiagn patent was probably in the late 1930’s and some later in the 50’s by one german comapany