A hood member 12 of a snap-fit male electrical connector 10 is inserted and retained in a through hole 21 of a panel 20. A locking arm 15, having a resilient retaining claw 16 is provided on the peripheral wall face of the hood member 12. A guard 17 is formed in front of the stopping claw 16, so that even if a female connector 30 is pushed diagonally and makes contact with the guard 17, the locking arm 15 is prevented from being bent downwards, thereby accidentally releasing the connector 10 from the through hole 21.