These precision tubes form the internal structure of the finished pen, providing the strength, stability, and alignment required for a professional-quality result. Manufactured to match the original kit specifications, the Over & Under Shotgun Tube Set ensures proper fitment and smooth assembly, allowing you to achieve a durable and attractive finished writing instrument.

Whether you’re working with hardwoods, acrylics, resins, antler, or hybrid blanks, this replacement tube set is an essential spare for any pen maker’s workshop.