
A door hingedly connected to a suitable frame structure by means of hinge structure for enabling the door to be swingably moved about the opposite side extremities of the door. A first pair of rotary bearings are mounted on the upper and lower ends of the door adjacent one extremity thereof, which bearings have arcuate slots therein which coact with arcuate projections provided on the frame and disposed for coaction with the first pair of bearings. A second pair of rotary bearings are mounted on...











