You have successfully added from to your part list.
Foil Integrity: Foil is available in three classifications of integrity
Vacuum Tight: The foil will have no detectable leaks. This will be tested with a helium mass spectrometer leak detector with a sensitivity of 1 x 10-9 atm-cc/sec. Thickness range: 0.0003 – 0.010 inches
Optically Dense: The foil will be impenetrable by light. This will be tested by illuminating one side of the foil over a restricted area with a high intensity light source, and then viewing from the opposite side in a darkened room.Thickness range: 0.0002 – 0.010 inches
As-Rolled: The foil is supplied in as-produced condition, and is not inspected or guaranteed to be vacuum tight or optically dense.Thickness range: 0.0001 – 0.010 inches
Surface Quality: Material will be uniform in quality and condition, clean, sound, and free from foreign materials, and from internal and external imperfections that affect the fabrication or performance of parts.
Surface Finish: The surface finish of standard foils shall be 40 microinches Ra or better. Various thicknesses may be available in different surface finishes. Please consult Materion Electrofusion for availability.