Can I weld this directly to my other exhaust components?

Yes. The flared ends are designed for welding. Clean the joint surfaces with a wire brush before welding to ensure a solid bond.

What thickness is this tubing?

Wall thickness is not specified in the product data. Measure or contact the supplier before ordering if thickness is critical to your fitment.

Do I need to paint or seal this before installation?

Stainless steel doesn't require primer or paint for corrosion protection. If you want a polished or coated finish, that's up to your build preference — bare stainless will patina naturally over time.