They come from Etsy artist Dulcecalaveritas and are handmade from leather with an alligator clip to attach it in your hair. They measure 3″ across. There’s also a larger version that is made with sparkly fabric and vinyl if you want something extra special.
Be the Bat Girl! Look amazing. Put one on your kitty and call it Hello Batty! Then make toys based on Hello Batty and sell them. Should be a big hit.