Feature: 1. MORE STABLE: Rolling pen is about 24cm long, which is long enough for you to use. And both ends of the pen are embedded with metal for counterweight. 2. BRAIN TRAINING: Suitable for both children and adults. You can use this pen to train your hands, eyes and cerebellum, so you can improve your concentration, memory and learning ability. 3. LED FLESH LIGHT: The surface has a frosted, non slip design for a comfortable grip. Equipped with LED flesh light, it can be more cool light at night. 4. PERFECT GIFT: You can give this gaming finger pens as a gift to your friends, relatives, colleagues, classmates on Thanksgiving, Christmas, New Year, birthday, etc. 5. RELIABLE MATERIAL: Rotating pen is symmetric design, the pen made of durable plastic, metal and silicone, which is reliable and sturdy and can be applied for a long time. Specification: Item Type: Rolling Finger Pen Material: Plastic, metal, silicone Size: Approx. 24 x 1.5cm / 9.4 x 0.6in Battery: 1.5V 43mAh 6 x LR41 button cell (built in). Package List: 1 x Rolling Finger Pen Note: The pen cannot be used for writing.