The Kneass design combined with the regular reverse die. This appears to be the only pattern using this obverse die which is believed to be a true original actually struck in 1838.
The only example known is in the Mint collection. The Mickley 2160 listing for a second example has been discredited. The lot sold for only $8.50 to Colonel Mendes I. Cohen and an example of this pattern was not included with the 1875 sale of his collection. It was probably a J72/P75, an example of which was in the Cohen sale.
Photo courtesy of the National Numismatic Collection of the Smithsonian Institution.