Electrical connector with one-piece first casing

An electrical connector, configured to be assembled with a joint, the electrical connector comprising:

• an outer casing, comprising a first casing and a second casing, wherein the first casing comprises an accommodation portion, a threaded portion and a connection portion, the accommodation portion and the threaded portion are integrally connected to each other via the connection portion, the accommodation portion is configured to be assembled with the joint, the threaded portion and the second casing are screwed with each other, and the first casing and the second casing together form an accommodation space;
• a seat body, disposed in the accommodation space;
• and
• a plurality of insulation-displacement contacts, fixed to the seat body and extending to the accommodation portion;
• wherein the electrical connector further comprises an annular wire holder, the annular wire holder is disposed in the accommodation space, and the plurality of insulation-displacement contacts are inserted into one side of the annular wire holder;
• wherein the electrical connector further comprises at least one ground sheet, wherein the annular wire holder has an outer annular surface and a rib, the rib protrudes from the outer annular surface, the at least one ground sheet is movably disposed on the annular wire holder and is in electrical contact with the first casing, the at least one ground sheet has a positioning slot, and the positioning slot of the at least one ground sheet is configured to be engaged with the rib of the annular wire holder.