Type: Other Color: Yellow This is a pen holder that clips onto the cover with a grip. The cat part is about 2.3cm x 2.5cm. The part that holds the pen is spring-shaped, so it should be able to hold slightly thicker pens. The inner diameter is about 1cm in the photo. I measured it while it was still in the bag, so it's not exact. I've kept it stored since I bought it, so I don't see any dirt or scratches, but it's been stored at home, so please consider this if you are interested!