Multi-Block Multi-blocks are a versatile connector for fastening sheet material to the aluminium beams. The multi-block is inserted into the beam T-slot and fixed by turning through 90 degrees.A square nut is included, XC and XF M6, XD M5 for mounting the sheet material.,Screw length to be sheet thickness +22mm.,XC type also includes a push on clamp for an alternative method of holding the sheet material (suitable for sheet thickness 1 to 6mm).