A rigid or flexible tubing having uniform inside and outside diameters in the overall length. it is specifically designed to prevent any undesirable flow of current between conductors and other objects. includes shrinkable type tubing, items in bulk and in specific fabricated lengths (cut to size). excludes items not having rated electrical characteristics. also excludes bushing, sleeve; cable nipple, electrical; conduit (as modified); insulation sleeving, electrical, special purpose; insulation sleeving, thermal; sleeve, marker, cable; sleeving, textile, electrical; tubing, glass; and tubing, nonmetallic.