Ohio Rev. Code Ann. § 4585.12

Judges of county courts within their respective areas of jurisdiction shall have jurisdiction under sections 4585.01 to 4585.14, inclusive, of the Revised Code, when the amount claimed does not exceed five hundred dollars, and as near as may be shall proceed according to the rules prescribed in said sections for other courts. The bill of particulars of the plaintiff shall be verified by his affidavit.