Holes, notches, indents, dimples, diamond indents (embossed), serrated ends, double diameter, coped (radius) ends, open seam gap (keyway), part number stamp, logo stamp, and spin weld assembly.
Welded Seam

Holes, notches, indents, dimples, diamond indents (embossed), serrated ends, double diameter, coped (radius) ends, open seam gap (keyway), part number stamp, logo stamp, and spin weld assembly.