Its great triangle - double inking edge and lifting edge, you dont get this kind in Europe ,
long time ago KUM made them with double inking edge ...
and this was/is new old stock, made in USA, now they make these in India...
... its light enough so it doesnt slip as much as heavier ones on tilted drafting table
but, yes, on the other hand they can break easier ...
Pentel S520 Sign Pen Black ink color fine point fibre tip pen 12 pcs in box.