What are the threads on an Accubrake?

Thread pitch for Accubrakes are dependent on the barrel contour and model of Accubrake®. Accubrake® - Contour Thread #1 contour 1/2-28 #2 contour 9/16-24 #3 contour 5/8-24 #4 contour 11/16-24 Accubrake® ST - Contour Thread #1, #1 MOD, #2, #2 MOD contour 1/2-28 #3 contour 5/8-24 #4 contour 11/16-24