the strike plate assembly 32 may be a t shaped plate made of rigid material such as aluminum and include a plurality of mounting apertures 38 that are used with fasteners such as screws bolts or the like to mount the strike plate assembly 32 at a predetermined height that is parallel and in the same plane as the locking bar 12 on the gate 11 to insure engagement of the latchbolt 18 in the latchbolt receiving aperture 36 the t shaped configuration of strike plate assembly 32 having legs of predetermined length with beveled edges insures that certain of the fasteners are blocked to prevent removal so that the strike plate assembly 32 cannot be removed when the gate 11 is in the locked position by virtue of actuating cylinder lock 14 with a key 42 which can be accessed from either side of the gate 11 so that there is a double cylinder key actuated lock from each side of the gate 11 rotation of key 42 within the cylinder lock 14 causes the pawl lock mechanism 16 to be rotated which has retracting bar 40 connected directly to the latchbolt 18 that is spring locked rotation of the key 42 within the cylinder lock 14 will withdraw latchbolt 18 against the spring tension a sufficient distance to.