"alta47" wrote in message
. ..

But, I have a 15-foot (+/-) bright yellow "plastic?" flexible gas supply
line in the basement of a property I own. It was installed a few years
ago when I had a new gas boiler/heater installed to replace the oil-fired
boiler for the cast iron radiator heating system in the home. So, I know
these exist, and I know they are code compliant.

I have one such line in the basement too. Professional installation is
probably required (local plumbers in my case) due to the fittings at either
end, I'm guessing. Made short work of extending the gas line 10 feet as it
easily goes over & under things that are always in the way.