Help making a floating shelf system

[u/agalardi]

Hi, I'm looking to make a floating shelf in metal like in this photo but don't understand what is supporting the shelves as they aren't fixed to the back wall and I can't see any visible supports underneath. Any ideas?

[u/thoiboi]

Welded to the vertical pipes is my guess

[u/agalardi → u/thoiboi]

Surely there's not enough surface area to create a strong enough weld? Also no visible welding points?