Works as intended. I used 6mm x 6mm staples to fasten a very thick phone cord (7/32") and it fit a little loosely, although another poster claimed the size only fit 3/16" or less at the time , as the packaging says "up to 1/4 inch". I ended up not liking the look of the slack wire and bulky clips and removed most of those T59 clips from the wall and used another pistol, an Acme, instead 37AC with 37AC brackets to hold the wire These larger AV brackets were even looser but so thin that they couldn't be seen from afar and the wire reached to the bottom of each bracket and rested almost entirely on the Socket so the wire practically disappeared. I now doubt the need for insulated staples when special staplers can safely insert staples to a predetermined safe depth. Now I'm thinking the last way. However, there may be some appl ments where isolated brackets are still required. I've found the Acme 37AC to be useful for just about any AV cabling situation, but a perfectionist should have a dedicated stapler that's perfect for any type of cable.