I have a selection of cap badges that I picked up during a test purchase some years ago. Instead of having pin clasps at the back they had loops on either side like the shank of a blazer button. I recently ran across a picture of a cap badge with what looked like cotter pins or bobby pins run through the loops. Does anyone know how this type of fastening works? If I can figure that out then I can figure out how to sell them or more likely give them away. Respond at your leisure.