Can someone identify this 1/2" knockout hole plug?

[Gigfy]

I like these knockout hole plugs but can't find where to get them. They fit a 7/8" hole (i.e. 1/2" knockout). They are two piece screw together plugs (a female threaded cap and a male threaded plug) which seal well.

Pics attached. Thanks.

 

[mm08822]

Consider Mcmaster# 7280k161..... it's close, but only 1 piece. Thread it into a hub or supply your own locknut.

 

[Norcal]

Check into 22MM KO seals. They look like IEC style fittings.

 

[Gigfy]

Thank you both. Very helpful.