Amazingly small and super bright 3-1 (Run-Turn-Brake) rear indicators. Engineered in Germany with SMD-LED technology. Die-cast housing with 8 mm (M8) thread. Tinted glass with 0.4″ (11 mm) diameter. For use on HD Softail, Dyna and Sportster fender struts we recommend to use Kodlin Turn Signal Adapters part #s 2020-1923 or 2020-1924.. Some applications may require the use of a load equalizer.. Universal fit on 12 volt applications..