Abstract: A combination padlock with revolving cover having a baseplate having an upper side, a lower side, a front side, a keypad on the front side, and a pillar formed on the front side. A revolving cover of a basically same contour as the baseplate has a rear face contacting the front side of the baseplate, a front face, a round opening, and an arc groove defined in the rear face thereof. A central cap has a side wall received in the round opening of the revolving cover and fixed to the baseplate, and a peripheral covering and resting on the front face of the revolving cover.

Abstract: A door locking system with an idle handle has a door panel having a front face, a rear face, a hinged side, a free side, an upper side, a lower side, and an electronic lock and a mechanical lock installed in the door panel respectively having a keypad and a keyhole on the front face. The system further has a level toggler, at least one bolt, a chamber defined therein, a handle seat, a handle lever, a latch lever, a linking arm, a swivel pillar, a paddle shifter, an upright toggler, and an handle lever resume spring.

Abstract: An emergently openable safe door having a mechanic lock and an electronic lock. The mechanic lock has a shell and a cylindrical plug in the shell. The plug has a primary keyway for a primary key and an emergent keyway for an emergent key. The mechanic lock and an electric lock are able to respectively be opened with a primary key and enter cod normally and be opened with the primary key and a emergent key emergently when the electronic lock thereof malfunctions or an enter code thereof is forgotten.

Abstract: A dual key bi-step lock having a shell and a cylindrical plug in the shell. The plug has a primary keyway and a secondary keyway and at least one set of primary pin stack and at least one set of secondary pin stack between the shell and the plug, respectively coupling with the primary and the secondary keys. a longitudinal stage is formed on a cylindrical surface of the plug. An involute side face extending from the stage to the cylindrical surface of the plug. The primary key is able to dive the plug to a position of first step open at which the stage is stopped by the key pin of the secondary pin stack. The secondary pin stack is unlocked by the secondary key and the plug is able to be further driven to a position of second step open by the primary and the secondary keys from the first step open.