GBX Twin-Pack - Developer and Fixer Concentrate for Manual (Hand Tank) Processing. 1 x 37 oz. bottle Developer and 1 x 37 oz. bottle Fixer. Makes 5 Liters Developer and 5 Liters Fixer. Designed for the manual processing of all Carestream dental X-ray films (both intraoral and extraoral). Replacement for 190-1859 Twin pack - makes 5 liter each developer & fixer