ISO 6118:2006 specifies performance tests of brake cups and seals for hydraulic braking systems for road vehicles. It does not include requirements relating to chemical composition, tensile strength and elongation of the rubber compound. Disc brake seals are not covered by this International Standard.

ISO 6118:2006 is applicable to moulded seals (cups or double-lipped type gland seals), 60 mm in diameter and smaller, compounded from rubber, for use in hydraulic actuating cylinders employing road vehicle non-petroleum base hydraulic brake fluid conforming to the requirements of ISO 4925.