Check out the following link: http://www.appletonelec.com/pdf/TW1thruTW2.pdf
Look at page 9 of the catalog (page 8 of the .PDF) for the 92TXXX box connectors. These are my favorite for several reasons.
- First, once you've installed it in the box and inserted the conduit, you simply tighten the nut. You don't have to worry about holding the body or a locknut with another pair of pliers to get it tightened.
- I find them easier to deal with in general since your wrench is always outside of the box.
- The connector's opening inside the box slightly overlaps the end wall of the pipe which seems to afford a little additional protection against wiring chaffing over a burr that was left on the pipe after cutting.
- It is much easier to install this type in adjacent KO's than the types that require a locknut inside the box.
Just my opinion/preference. On the other hand, I've only been able to purchase them at electrical supply houses, not the big box stores.
One last thing: Set screw and comp. fittings that attach with a locknut have a stop in them that is outside of the box. This Appleton connector allows the pipe to protrude into
the box before bottoming out. That said, add a 1/4" to your pipe lengths to account for this.