within the female portion 11 the first conducting set 113 can be plug type or screw type the first conducting set 113 of the present embodiment is plug type the first conducting set 113 includes a first conducting member 113 a and a second conducting member 113 b made of metal with good conductivity the first conducting member 113 a and the second conducting member 113 b are fixed at the top part of the accommodating space 111 and respectively act as the anode and cathode the first conducting member 113 a can be disposed on the center position of the top part of the accommodating space 111 the second conducting member 113 b can be disposed around the first conducting member 113 a in an annular shape the female 11 portion of the present disclosure is designed correspondingly to the light source 5 and can be modified to meet different forms of the light source 5 the male portion 12 is made of material such as plastic the male portion 12 is integrated as one piece with or connected by assembly to the female portion 11 a second conducting set 121 is disposed on the male portion 12 the second conducting set 121 of the present disclosure includes a threaded sleeve 121 a and a contact plate 121 b the threaded sleeve 121 a and the contact plate 121 b are both made of metal with good conductivity the threaded sleeve 121 a.