Those Zig Zag Scissors

  

These scissors are actually called “pinking shears”. 

The sawtooth blade creates a “zig zag” cut. 

Why would you want to add a pair of pinking shears to your sewing box?

Woven fabrics fray.  Many times, they fray A LOT.  Cutting raw edges with pinking shears won’t prevent all this fraying, but it will limit the length of the threads that fray.  So, having a pair of pinking shears is handy for trim seam allowances and preparing the edges of some fabrics before your wash them.