A connector receptacle for connecting with a corresponding connector plug coupled with electrodes being used for performing EMG procedure on a patient is provided. The receptacle includes a first ball bearing pressing against a first end of a housing of the plug and, preferably, a second ball bearing pressing against a first end of the housing of the plug when the plug is connected to the receptacle for exerting a retention force against the plug. The first and the second ball bearings are pressed against the first and the second ends respectively by using a spring force generated, for example, by a retention band.