The height is the belt width. It supports singles up to 4 cm in height. If it is thin, please secure it with the included Velcro. Please secure it firmly. The cross loop at the top is a snap button, so be careful not to detach it. We are also considering a model that supports slightly thicker belts. This one is small. Thank you for your understanding. The 4th photo shows it attached to a Foxfire. When attaching it to a narrow and thick area like this, it is recommended to purchase separate Velcro instead of using the included one to secure it. The subsequent photos are for comparison. The flap is designed not to sag, making it easy to put things in and take them out. Although it is described as small, even a medium-sized one can fit thinner pliers. If you are concerned about the Velcro on the back falling off, please contact us after purchase. We will make a hole so you can connect it with thread or something similar. Thank you for your understanding. *Pliers are not included.