The outside diameter (OD) is 9/16"

all tig welded and come plumbed for Harley motorcycle

Key Features and Performance Advantages:

compatible with stock axles from 1977-2003 or custom options

Chrome plated duplicate of original Harley-Davidson studs

1 inch Clutch Control Lever - Black Brand_Custom Cycle Engineering The outside diameter (OD) isGMA offers an all new look for handlebar controls for every possible application. The universal style are intended for those building a custom bike and choosing to eliminate switches from the bars. GMA offers a switches and buttons design for both the clutch and brake side. Available in black, polished and chrome finishes. Clean design makes these assemblies a great choice for custom applications CNC machined Assemblies fit most 1" diameter handlebars