Abstract: A composite sliding gasket for joints of high-pressure pipes is basically formed by a rubber part and by a rigid ring—having the function of flange—that is designed to draw the gasket itself from a resting position or seat to a working position or seat by an external pipe or hole that is axially fitted on an internal pipe or barbed fitting. Compression of the rubber part of the gasket, which guarantees fluid tightness, is obtained thanks to the presence of a purposely provided conical area pre-arranged on the barbed fitting between the resting seat and the working seat. The gasket includes a rubber ring fixedly coupled to a coaxial flange made of rigid material of plastic or metal or other suitable material, the gasket being designed to seal a coupling with play between the internal pipe and the hole within which a pressurized fluid can flow.