Simon's stainless flange assemblies
Here you have a connecting piece with 2 pieces. flanges and gasket.
Simon's Flange Collection - Exhaust Flange
Here you have 2 flanges with stainless steel welded and a gasket in the middle. The 2 pipes can be used to weld edge to edge or to attach an assembly piece and fasten. They are of super good quality and stainless steel material.