Seems to be about the same thickness as the originals, which is to say, very good. My older, original burners had plastic spider guards; these came with stainless steel screens on the burners instead.
The new burner kit solved the problem of uneven and poor grilling. The Weber instructions were poor and required me to look up help on the internet to confirm that I had installed everything correctly.
perfect fit, works great, easy installation with very clear instructions provided. Glad I spent the money on weber parts and not some "universal" set up. paired with the favorizers and the new weber grates I found at a local thrift store I've basically made my circa 1993 grille new.