The present invention provides a connection device for connecting an electrical device. The connection device includes a dielectric housing having a slot formed therein to allow the electrical device to plug in. The slot includes a top surface and a bottom surface. A first bulge portion and a second bulge portion extend downward from the top surface. A third bulge portion and a fourth bulge portion extend upward from the bottom surface. The first bulge portion corresponds to the third bulge portion for clamping the electrical device. The second bulge portion corresponds to the fourth bulge portion for electrically coupling to the electrical device.