mode of attaching plug 40 it can be temporarily attached at temporary abodes of the user such as hotel room and motel room doors to disengage plug 40 and its attached lanyard 44 the above described process can be reversed to release wire 50 from between annular flange 32 and surface 38 of door 12 one of the optical characteristics of a conventional door viewer of the type illustrated in fig1 and 2 is that blockage of a source of light transmitting light directly through the door viewer can be detected by a person outside of the door however when ambient light interior of the door is the only light transmitted through the door viewer no or little change in intensity of the light transmitted is detectable if a person were to place one 39 s head in position to look through the door viewer from the inside to the outside as shown in fig3 it is assumed that a source 60 of light would transmit light directly through door viewer mounted within door 12 in such event if a person 62 were to look through the door viewer the transmission of light from source 60 would be blocked the resulting change in intensity of light detectable by a person 64 outside of door 12 would provide an indication of the presence of person 62 the present invention is particularly suited to avoid such indication of the presence of a person 62 when a person 62 decides to look through door viewer 10 the person would block direct light transmission from source 60 through the door viewer and only ambient light would be available for transmission through the door viewer when in.