?High quality material?Made of high quality material with Japanese motor. Effective and durable. ?Quick operation & precise?chuck speed 12,000rpm?; Pen head diameter: 2.35mm. Even though small size has big power, The cordless rotary tool has low torque and is only suitable for light grinding, engraving, etc. ?Electric?powered by 4 x AA type batteries (not are not included in the package). Easy to handle & riparmia of force. ?Widely used? Applications include engraving tools, sporting goods, toys, phone chargers and delicate personalization of jewelry, watches and glassware (Perfect gift for birthday, holiday, Christmas and other special occasions) ?Quality guarantee? If you have any questions, please contact us immediately and we will respond to you within 24 hours. If your products arrive broken, we will immediately send you a new one or a full refund. If you are not satisfied in any way, our products are backed by a 100% money back guarantee. Electric engraver pen with diamond tip