Gibson Norlan era Bill Lawrence designed neck pickup from Les Paul Custom, circa 1978.
Bill Lawrence was ahead of the game when it came to pickup design.
These "Tarback" pickups - Official name was Super Humbucking and was originally introduced into some Gibson guitars in late 1972 / early 1973.
The Tarback moniker came from the black epoxy type of potting material that Bill did to anticipate the higher volumes / higher amplification volumes in the 70's.
Like most of the humbuckers made by Gibson in the 70's, they are labled as "T-Tops" but they are NOT the same pickup as the true T-Top humbucker / wound the same as a traditional T-Top. The "T" was mold mark that supposedly meant Top of Coil.
These Tarback pickups used Ceramic Magnets while the T-Tops used short Alnico 5's.
And the construction was different too.
This "Tarback" came out of a Late 70's Gibson Les Paul Custom and is in good cosmetic condition with the normal amount of oxidation of the gold hardware.
This pickup reads 5.17k - by design, this Neck pickup should read close to 5.2k