Probation supervision fee (Pen. Code, § 1203.1b) may not be applied to the supervised release portion of a split county jail sentence because it is not “probation.” Defendant was convicted of sale-related drug offenses and resisting arrest. Priors were found true. On appeal he raised various issues, including a challenge to a probation supervision fee. Held: Fee reversed. Section 1203.1b allows a trial court to order the defendant to pay all or a portion of the costs of probation supervision upon finding an ability to pay. Section 1170, subdivision (h)(5)(B)(i) provides for mandatory supervision of a defendant by the county probation officer when a split sentence is ordered. However, the language of the subdivision “pertains to the nature and manner of supervision by the probation officer over the defendant,” it does not authorize imposition of supervision costs under section 1203.1b. Payment of probation costs under section 1203.1b may not be made a condition of probation because such costs are collateral to the grant of probation. As such, the language of section 1170, subdivision (h)(5)(B)(i) should not be broadly interpreted to include authority to impose such costs in cases of mandatory supervision. Subsequent to the amendment which added subdivision (h) to section 1170, the Legislature amended section 1202.45 to apply its parole revocation fine to mandatory supervision revocation, even though section 1202.44 already allowed such fines where probation is revoked. Given the Legislature did not similarly amend section 1203.1b to apply to mandatory supervision, this indicates it did not intend such application.