Size: 40 x 40 mm, suitable size will not occupy much space but will help you storage your pens. 5 pieces pen loop inclueded, meeting your demands. Warm Notice: The black pen loop is an enlarged version, the elastic band size is : 2 x 2cm. Colorful pen loops are the normal version, elastic band size is: 2 x 1.5cm. More details please refer to the picture. Adjustable Loop Diameter: The elastic pen loop could accommodates many sizes of pens and pencils. Convenient to Use: Perfect for journals, notebooks, planners, calendars and it can clip on these books. Anti-Lost: Pen loop holder could prevent your pens from losing. Easy to Use - Peel the sticker on the back of the artificial leather, then adhesive it to any surface of the books where you need to hold the pens.