These crucibles are manufactured from zirconium. Available with slide-on ring, snap-on ring or flanged rim.

• Slide-on ring: A removable ring that slides up, fitting approximately 5,08 mm below the top of the crucible
• Snap-on ring: A removable ring that snap-fits into a machined groove located approximately 5,08 mm below the top of the crucible
• Flanged rim: A formed rim, integral to the crucible (not welded on), at the crucible's top edge