3+3, Set of 6. Excellence in materials and craftsmanship are the hallmark features of these classic machine heads. The die cast base provides a rigid foundation for the gear and worm, assuring perfect alignment and mesh. The pearloid buttons are attached with a tension screw to provide the feel of your preference. A bearing over the worm shaft provides additional support and enhances the smooth performance. Includes wood screws.3+3, Set of 6