There are a few things to consider when choosing the "best costume feather boas." The first is the material. Feather boas are often made of feathers, so it is important to choose a material that will not cause any allergies. The next consideration is the size. A good rule of thumb is to choose a size that will fit around your neck comfortably. The last consideration is the style. There are many different styles of feather boas, so it is important to find one that will fit your character and look good on you.