Kondor Blue 1/4 Inch Ball Head for Magic Arms, BlackKondor Blue 1 4 Inch Ball Head for Magic Arms, Black This 1 4 20 ball head can replace the 3 8 version. You can tighten this to cages or any accessories very tightly with a hex spanner through the slotted hole. This is compatible with most Magic Arms, Friction Arms, and Israeli Arms using a dual ball head system. Key Features 1 Ball Head One 1 4 20 screw Aerospace Grade Aluminum