Following production of the "5 Lines" type, the Mint created new reverse dies featuring just four vertical lines in each of the 6 major stripes on the eagle's shield.  This new "4 Line" style became the standard for heraldic eagle dollars for the remainder of dollar production through 1804.

When combined with the existing "Knob 9" dated obverse dies, a new sub-type of dollar resulted, and these coins have been labeled as the "Knob 9" type.

At MS63, the Cardinal Collection specimen of the BB-94 variety is tied with one other as the finest Knob 9 dollar ever graded.  (In fact, those two represent the ONLY "Knob 9" specimens ever graded as mint state.)  Superbly sharply struck throughout, the coin displays smooth surfaces lightly toned in shades of golden brown with bluish highlights.  Sparkling cartwheel luster abounds.