The FX Radar Chrony is a great little tool but if you use one then you will know its short comings:
1 It needs rubber bands to fit it
2 It changes point of impact
I have designed a Picatinny QR mount for it which resolves these issues
Its all 3d printed with a stainless steel through bolt
To adjust it use a allen key
It also fits on the Impacts Side Rail
It will come adjusted for the Saber Tactical rail as shown in the video: