If

is odd and

is such that

is

, there is a
![[2^{m+1}-1,2^{m+l}-2m-2]](/images/tex/5652.gif)
nonlinear binary code

having minimum distance 5. All the codes

have the same distance and weight enumerators as the usual Preparata codes (which rise as

when

. It is shown that

and

are equivalent if and only if

, and

is determined.