Covers for outlets in an electrical floor box are connected with an access plate by snap-fit hinge connections. The covers are swingable through arcs greater than 90.degree. during movement from a closed position to an open position or to an inward storage position. Cooperating pimples and dimples on...http://www.google.fr/patents/US5455388?utm_source=gb-gplus-shareBrevet US5455388 - Electrical floor box access cover
