A card holder for use inside an electronic device is provided. The card holder includes a holder body and a plurality of electrical connectors. The holder body is disposed with a card slot matching a nano SIM card. The card slot is configured to accommodate the nano SIM card or a memory card having a same appearance or shape as the nano SIM card. At least some of the plurality of electrical connectors are first electrical connectors whose positions match the positions of electrical contact points in the nano SIM card. The first electrical connector is configured to electrically connect to the nano SIM card or the memory card accommodated in the card slot. The plurality of electrical connectors are configured to electrically connect to the memory card.

An electrical connector is provided. The electrical connector is connected to the counterpart electrical connector. The electrical connector includes: an insulating housing having an annular portion; a first elastic member provided to the annular portion; and a second elastic member provided to the annular portion, wherein the first elastic member has a first region exposed on an inner surface of the annular portion and configured to contact a first member of the counterpart electrical connector, the second elastic member has a second region exposed on an outer surface of the annular portion and configured to contact a second member of the counterpart electrical connector, and the first elastic member and the first member are electrical contacts and/or the second elastic member and the second member are electrical contacts.

A connection terminal having a copper alloy as a base material, the copper alloy comprising Zn in an amount of 21 mass % or more and 27 mass % or less, Sn in an amount of 0.6 mass % or more and 0.9 mass % or less, Ni in an amount of 2.5 mass % or more and 3.7 mass % or less, and P in an amount of 0.01 mass % or more and 0.03 mass % or less, and the balance being Cu and inevitable impurities, wherein the copper alloy has: a 0.2% proof stress of 620 MPa or higher and 700 MPa or lower, and an electrical conductivity of 15% IACS or higher and 20% IACS or lower.

A rotary plug electrical connector includes a plug and a socket, both of which include power contacts and signal contacts. The plug is rotatable within the socket between operable and inoperable positions. The power contacts of the socket include opposed surfaces which are engaged by resilient blade power contacts of the plug. The signal contact of the socket preferably includes a pair of contacts, and the signal contact of the plug preferably is a bridge contact that engages the socket signal contacts in the operable position and disengages the socket signal contacts in the inoperable position. When the signal contacts are disengaged, no power is transferred by the connector.

A rotary plug electrical connector includes a plug and a socket, both of which include power contacts and signal contacts. The plug is rotatable within the socket between operable and inoperable positions. The power contacts of the socket include opposed surfaces which are engaged by resilient blade power contacts of the plug. The signal contact of the socket preferably includes a pair of contacts, and the signal contact of the plug preferably is a bridge contact that engages the socket signal contacts in the operable position and disengages the socket signal contacts in the inoperable position. When the signal contacts are disengaged, no power is transferred by the connector.

A socket strengthener, a board-to-board socket, and a board-to-board connector assembly. The socket strengthener (60) comprises a main body part (61), top surface cover parts (66) and lateral outer peripheral wall cover parts (64) formed by extending from the main body part (61), elastic arm parts (65) curving backwards from the ends of the lateral outer peripheral wall cover parts (64) and extending to the inner sides of the lateral outer peripheral wall cover parts (64). The top surface cover parts (66), on the side adjacent to the elastic arm parts (65) bend downward to form guide parts (662). Viewed from top to bottom, the guide parts (662) do not overlap with the elastic arm parts (65), and the bottoms of the guide parts (662) are lower than the tops of the elastic arm parts (65). The board-to-board socket comprises a socket body, a socket terminal, and the socket strengthener. The board-to-board connector assembly comprises the board-to-board socket and a plug matched therewith. Guide parts are formed by means of a bending downward on the lateral outer side of the top surface cover parts of the socket strengthener, and elastic arm parts are formed by means of a backwards bending of the free ends of the lateral outer peripheral wall cover parts. The elastic arm parts and the guide parts are displaced in lateral directions so as to increase the length by which the guide parts extend downwards, causing the guide parts to be able to protect the elastic main arm of the elastic arm part throughout the entirety of an insertion process.

A socket strengthener, a board-to-board socket, and a board-to-board connector assembly. The socket strengthener (60) comprises a main body part (61), top surface cover parts (66) and lateral outer peripheral wall cover parts (64) formed by extending from the main body part (61), elastic arm parts (65) curving backwards from the ends of the lateral outer peripheral wall cover parts (64) and extending to the inner sides of the lateral outer peripheral wall cover parts (64). The top surface cover parts (66), on the side adjacent to the elastic arm parts (65) bend downward to form guide parts (662). Viewed from top to bottom, the guide parts (662) do not overlap with the elastic arm parts (65), and the bottoms of the guide parts (662) are lower than the tops of the elastic arm parts (65). The board-to-board socket comprises a socket body, a socket terminal, and the socket strengthener. The board-to-board connector assembly comprises the board-to-board socket and a plug matched therewith. Guide parts are formed by means of a bending downward on the lateral outer side of the top surface cover parts of the socket strengthener, and elastic arm parts are formed by means of a backwards bending of the free ends of the lateral outer peripheral wall cover parts. The elastic arm parts and the guide parts are displaced in lateral directions so as to increase the length by which the guide parts extend downwards, causing the guide parts to be able to protect the elastic main arm of the elastic arm part throughout the entirety of an insertion process.

A female connector and a male connector are disclosed. The female connector includes a ring-shaped outer wall, a first terminal seat, a second terminal seat, and a third terminal seat. The male connector includes a front connecting block. A front end surface of the front connecting block includes a first terminal hole, a second terminal hole, and a third terminal hole. The first terminal hole has a first terminal supporting surface. The second terminal hole has a second terminal supporting surface. The third terminal hole has a third terminal supporting surface.

A female connector and a male connector are disclosed. The female connector includes a ring-shaped outer wall, a first terminal seat, a second terminal seat, and a third terminal seat. The male connector includes a front connecting block. A front end surface of the front connecting block includes a first terminal hole, a second terminal hole, and a third terminal hole. The first terminal hole has a first terminal supporting surface. The second terminal hole has a second terminal supporting surface. The third terminal hole has a third terminal supporting surface.

A contact includes a hollow box-shaped main body portion into which a plate-shaped counterpart contact is inserted in an insertion direction. A pair of inward slantwise elastic piece portions are provided in a manner extending in the insertion direction from a pair of opposed edge portions of the insertion opening of the main body portion into the main body portion. The pair of elastic piece portions have contact portions arranged in mutually proximal portions. A pair of restricting portions provided on the main body portion are arranged to restrict the amount of deformation of the pair of elastic piece portions when the counterpart contact is inserted.