"Airtight" Screw-on Plug for 2-in Electrical Plug Hole

This plug fills a 2-in hole through plywood while allowing an electrical cord to pass through.  This is designed for a router dust collection box, though it could be used for any other roughly-air-tight plywood box.

The plug is composed of 2 threaded parts that screw together from either side of the hole, with an insert that wraps around the cord to achieve rough air tightness.  One side of the hole needs to be at least ½" clear of walls to allow it to turn, but the other side can be placed immediately next to a wall or corner (see photos).  There are 3 variants of the female side provided for this purpose.

Working like a charm thus far and allowing far better dust removal from my DIY router box!