Gearbox/Drive bolt

Fittings that combine functionality, durability, and timeless design — essential for every listed or heritage building. Tummescheit manufactures and supplies historical gear mechanisms and drive bolts for windows, French doors, and custom applications from various eras.

These fittings have been used for centuries to ensure secure locking and remain indispensable components for authentic restorations today. Historically, they were primarily employed in windows and French doors. Whether for surface-mounted window mechanisms, lockable olive handles, or windows with overlapping frames, we offer historical gear mechanisms and drive bolts in a wide range of designs, materials, and finishes.