What size radius should I make for the slot for an aluminum block

What size radius should I make for the slot for an aluminum block m3 slot Buy FKU M3 Portable mini Bluetooth speaker with TF card slot stereo wireless speaker 3 W Bluetooth Speaker for Rs 1199 Only Genuine Products m358 slot These T-Nuts fit all our 20 series V-Slot and other 2020 profile aluminium T-Slot extrusion

m358 slot EXPANSION SLOT 1 X PCI Express X16 Gen slot 1 X PCI Express X1 Gen slot 2 X PCI slot Storage Support by Intel® H77 Express Chipset 2 X

m303 slot Elmech Components - Offering GN614 M3 38-16 slot drive ball locking Spring plunger smooth pin nose ball plunger with collar,spring plungers in Noida, As shown in the pictures, this washer can be used to bridge the slot on V-Slot or compatible extrusion to allow for the mounting of various components