Any Home Depot or Lowes will have these, two to a bag under $ 2.00
At HD they are in the same aisle with the romex clamps and all emt/rigid
fittings.



m wrote...

We call them cord grips at work. Pipe thread on one side, and a
compression gasket arrangement on the other. Available in metal or
plastic. Thomas&Betts and Hubbell are a couple of the brands we use.
They provide strain relief and a water tight seal to cords coming in
and out of electrical panels.