Getting ready to sell the house and the home inspector found missing Romex clamps all over. He wants them installed. To install the clamps I know about I have to take the wires out of the box, install the clamp, re-thread the wires and hook it all back up. Not looking forward to crawling around in the attic to do this. I looked on line and found a RAT 500 or TT 500 (I beleive they are made by Rack-A-Tier) that looks like it slides over the wire and pushes into the box. Does any one know about these and if this is how they work? Can they be used on metal boxes? Also, do they meet code (I live in NY if that matters)?

Thanks
Daniel