The ZUWIT car seat belt buckle holder only suitable for the following types of buckles: A buckle connected by a nylon belt that can’t maintain a fixed position by itself. Generally, you can see a strap with a length of about 1-2 inches /3-5 cm at the end of this type buckle. It is suitable for maximum buckle size 50*35mm / 1.9*1.3 inches.