A lamp socket assembly having insulation piercing and displacing contacts which make electrical and mechanical joints with the two conductors of an electrical lamp cord. The contacts have two pointed ends to pierce the insulation and a slot between to sever and displace the insulation from the contact which is arranged transverse to the path of the cord in the socket. An actuating lever, pivotally mounted to the socket body, is held in different ratchet controlled position ranges to hold the lever and socket in assembly and accept the cord end and then force the cord in to the insulation piercing and displacing contacts. A strain relief member is made to engage the cord when the lever is fully operated.