booby trap trip wire attachment

I wanted to make a trip wire with pull string booby traps but the tape would not stick to the string strong enough so I need an attachment to tie the string to and the and the tap/string

instructions-
1.attach one string of the booby trap to the door frame, cabinet, E.TC. with duct tape
2.tie the other string to one of the holes of the aattachment
3.tie string or tape through the other hole
4.secure the string or tape to the door frame, cabinet, E.T.C with duct tape