Paper white entredeux trim, approximately 2.9cm wide. 5mm ribbon can be inserted in the spaces, or it can be used as-is between two seams, for example, to join a sleeve and a gathered cuff. Looks the same from both sides.
These pure cotton trims are used to add detail to clothing or for edging cushions and bed spreads, etc. There may be a few loose threads which you would need to tidy up yourself with scissors. Other trims shown are available in the shop under the "Notions" section of the menu.