Another what is this? - 2 clamp parts?

[okeydokey]

I have had these for years and never found where they belong.
Both have screw clamping parts and slots so they must fit into something and then tighten against so if you know please share the info
Overall length about 10"
thanks

 

[MikeK]

These look like edge clamps, similar to the Bessey WBEKT5:

https://www.amazon.co.uk/Bessey-WBEKT5-Edge-clamp-Black/dp/B0034YR2CS

 

[Sgian Dubh]

I think the the notch in the cylindrical part slides over the bar of an F clamp so that it can be used to attach things like lippings to man-made board panels. I've come across something similar before, but always found them less than ideal because the F clamp tended to rotate as pressure was applied by the add-on edge/lipping clamp part. Slainte.

 

[recipio]

They are for putting pressure in the middle of a large panel which has sash clamps in place from edge to edge. The notch fits into the bar of a standard Record sash clamp. Mostly used for veneering they have been superseded by vacuum presses.

 

[okeydokey]

Thank you all - Having tried on a Record sash clamp I can see how they work now.
Not sure I will be using them anytime soon but at least they are no longer in the junk category.