Esbiothrin (CAS number 260359-57-5 ) is a mixture of the same two stereoisomers, but in an approximate ratio of R:S = 1:3.

WHO Specifications and Evaluations for Public Health Pesticides.

Esbioallethrin or S-bioallethrin (CAS number 28434-00-6 ) is the pure S-form (that is, the wedge in the structure as shown in the box points down).

[2] The name bioallethrin was a common name approved by the British Standards Institution and published in[3].

BS 1831 has been withdrawn, and the common name has been adopted by ISO.