Introducing the Light Button Pen: A Handy and New Tool. Simple Pen with Light Button This pen has a button that turns on a light, making it useful in dark places. Easy to hold for writing This product is designed to fit well in your hand, so you can hold and write with it for a long time. Easy to take anywhere. This device is slim and lightweight, great for everyday use. It’s perfect for work, school, or when you’re out and about.