A Cutter also known as a flag,  is used to “cut” the light and define the area lit. You can use a cutter to create a hard or soft edge, depending on how close to the light it is placed.
Floppies have an extra layer of material sewn to one edge and held in place with Touch Fastener until needed at which time the Cutter becomes twice its original size
Some technicians will use special names depending on the size or shape of the flag, but there is no penalty for switching the terms “cutter” and “flag.”  Some of the other names thrown around include
Charlie Bars;  Meat Axes; Blades
 
DMS Makes their Cutter flags with
Grade 304 10mm Stainless Steel tube 1.2mm wall
Crossbars and corner braces on large sizes to keep the frame sturdy.
10mm Pin
Size of the frame 4 Feet by 4 Feet
Covered in Heavy-duty Brushed twill solid Fabric or any fabric you desire.