I design this thing to put trundles under my table stands.
(the trundle support size is: 60x75mm & my table stands are 35x35mm)
the spacing between the holes of the trundle support are 55mm & 40mm.
That thing is design to be used with Ø3,40mm nuts, Ø6,95mm bolts and Ø3,40 wood screws.
I did an home-made mini Laser CNC, I have an Alfawise U30 3D printer, I am curious, interested to electronic, hacking, useful designs & everything about making.