ADM MDS Series Dovetail Adapter.
Attach accessories directly to a MDS series dovetail bar. Incorporates a split clamp design that grips the dovetail bar along the entire surface of the saddle and will not dent or scratch the dovetail bar. The dovetail clamp has a large “T” handle locking knob for tool free operation, spring loaded jaws, anodized aluminum and stainless steel construction.
Handy for attaching other items to your bar. I bought these to mount a guide scope on top of my main scope but changed scope which already had attachments. These are normally £40 each.