This is the hardest, most secure sunglasses case you can buy. This is a clamshell design glasses case, which snaps open and shut with a spring hinge. It is lined with a soft felt on the inside, and a hard outer covering to protect whatever you put inside. It is also quite large, most glasses and sunglasses will fit inside. They come in a variety of vibrant colors to fit your life style. This one is yellow. The inside measures 154mm wide, 64mm long, and 64mm tall.