Bare Knuckle Performance 39mm Fork Tube Extensions For Harley Give the front of your bike a lift without swapping out the entire front end. The Bare Knuckle Performance 39mm Fork Tube Extensions extend the effective length of your fork tubes by 1 or 2. The perfect way to subtly adjust the attitude of your bike. Features: Precision machined aluminum Witness marks make fine height adjustment quick Choose from 1 or 2 extension Complete with O-rings Black Anodized 100 Made in USA