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"I can't wait to bag me a deergoose!"
-John Leguizamo
The Pest
"Why would you ever talk?"
-Random
there are some that have a second hole without the ratcheting piece of metal in it simply used to hold the excess , you might try looking for one of those types, put it through backwards and it doesnt hole either, at least in MOST cases.
home depot, lowes, any of those home improvement labrynths have them, some places sell versions a couple feet long
later
Tom
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What everyone seems to forget is that once we look past race, religion, gender, and all that, everyone on this planet is first and foremost...
...a PERSON
I suggest you cut away a good sized hunk of these and replace it with a cured piece of latex or sewing elastic. Use the black ties for more contrast against the skin and ease of blending a substitute stretchy center. If you use them the way I suggest, you won't really be able to see the substituted center.
For shots of the cable tie in the killer's hands, or shown as he lunges at a victim, the real deal is ok. Once you have the cable going around the neck of the victim, switch to one gaffed up to be safe.
If you are at all skilled with molding and casting, you could make duplicate ties out of pre-colored black liquid latex.
Not the only solutions, just what comes to mind.
Above all, don't rely on the attacking actor being "careful" - at worst the victim actor could be harmed, at best he'll get ticked off and quit on you - never a good thing. We ask a lot of actors, but take care of them, we can't make movies of empty sets! 
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Jeff F - Moderator
Magic and FX
Amazing the Masses
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"I can't wait to bag me a deergoose!"
-John Leguizamo
The Pest
"Why would you ever talk?"
-Random
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Andrew Simpson
Big Hurt Productions
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