A glazing bar, primarily for security screening, is made up in composite form from a first slab 1 and a second slab 7. The first slab 1 has firmly anchored therein the head of a T section of metal, of which the stem forms a central flange 4 which engages in a slot in the second slab 7 and may be secured in position by fixing screws 13. Then fully engaged, the two slabs have opposed faces which are partially covered by resilient pads 6 and 11 and which form a glazing recess for receiving the edge of a sheet of security glass or other panelling. Other constructions are illustrated in other figures.