A Penal Code section 667.5, subdivision (b) prior prison term enhancement is based on the fact of a prior conviction, rather than a prior prison term, and can be used to aggravate the sentence on the underlying felony only when the court strikes the punishment for the enhancement. Appellant was convicted of numerous serious and violent felonies, as well as weapons enhancements. Following the jury trial, the court found three prior prison term allegations to be true. Appellant was sentenced to an aggravated nine-year term on one of the offenses, plus twenty-five years to life for a weapons enhancement and one year for each of the prior prison term enhancements. The court rejected the People’s argument that the nine-year sentence resulted from the court using the fact of the conviction to aggravate the term and the prison terms for the enhancement. The court found the present case indistinguishable from People v. Prather (1990) 50 Cal.3d 428 and People v. Jones (1993) 5 Cal.4th 1142, which held that the section 667.5, subdivision (b) enhancement is based on the prior conviction and not the prison term. Under this definition, Penal Code section 1170, subdivision (b) prohibits use of the enhancement to impose an upper term as well as for the basis of the sentence for the enhancement. (Cal. Rules of Court, rule 4.420 (c) is in agreement.)