The Double Diamond is an extremely strong retractable grille making it very hard to be penetrated.  The security doors small gap design is specifically designed for use in the protection of emergency exit doors.   The closely constructed lattice, coupled with a large shielding plate, prevents the high security emergency exit lock being accessed from the attack side (outside). Uses a thumb-turn lock from the inside to allow quick exit in an emergency.   The lock post design is covered by a protective sleeve, making it very hard to pry open.  The close lattice is ideal for the preventing of smash and grab style raids. Available in a variety if widths and in heights up to 2000mm.