A flash memory device includes a control board with a circuit board and a plug connecting with the circuit board, and a case enclosing the control board. The circuit board has two opposite surfaces. The plug includes an insulative housing and a number of contacts retained therein. The insulative housing has a tongue extending in a front to back direction. The contacts include a number of first contacts and a number of second contacts. Each first contact has a nonelastic contact portion and a tail portion arranged on the circuit board. Each second contact has an elastic contact portion located behind the nonelastic contact portion along the front to back direction and a tail portion arranged on the circuit board.