From the manufacturer:
This HotStamps Numbers & Symbol Set is the ultimate for personalizing your wood burning projects. This set includes 24 individual metal number and symbol stamps, which can be attached to any standard threaded Walnut Hollow hot tool by simply screwing on and off with pliers. These versatile stamps can be used on a wide range of materials, including wood, leather, fabric, and more, making it the perfect tool for any crafter or artist. With its easy-to-use design, you can quickly and easily personalize any project with your own unique touch. Don't settle for boring designs - take your creativity to the next level with the Walnut Hollow HotStamps Numbers & Symbol Set, plus our full line of wood burning tools and surfaces, including live edge rounds and planks.