On 2006-02-08, Chris wrote:

We just had a pro redo some of our gas, and all the new lines he put
in are the flexible kind.

There's a big difference between flexible gas pipe (corrugated
stainless steel) that can be used in place of rigid pipe, and flexible
gas appliance connectors that should only be used between the
appliance shut-off valve and the appliance.

Cheers, Wayne