Used for a perfect finish when replacing OEM fender strut mounted turn signals with Kellermann, or any other aftermarket turn signal, with M8 mounting studs; Note: Kellermann Atto, Micro S and Rhombus S turn signals require 563156 (20mm OAL) or 563157 (40mm OAL) M8 to M5 adapter studs
Fits: > 02-21 most Softail, Dyna, Sportster