This is a cotton book cover. The lining is unbleached sheeting. A medium-weight interfacing is applied, giving it a moderate thickness. A fabric band is attached for adjusting the thickness. The bookmark is made of synthetic leather and features a macaron-like covered button that serves as both a weight and an accessory. When open: 30cm x 16cm When closed: 12cm x 16cm However, the inner dimensions will be approximately 5mm smaller, depending on the thickness of the fabric. ★If you are purchasing multiple items, please let me know in the comments. ✳We will discount 100 yen for each additional item. For example, if you buy 3 items, you will receive a 200 yen discount. If you buy 5 items, you will receive a 400 yen discount. We will ship them together. Larger sizes are available.