Servo motor spline adapters?

[Espeefan]

Mario, I'm not sure that anyone offers a metal adapter spline that will make use of the original plastic servo arm, but why not upgrade the entire arm to an aluminum piece? You can find double ended aluminum servo arms all over the net, for many different brands of servos. What brand have you got there? I couldn't see the servo sticker in the video, with the name. Is it a cheap brand X servo?