1.1 This part of EN 10253 specifies the technical delivery requirements for seamless and welded butt-welding fittings (elbows, concentric and eccentric reducers, equal and reducing tees, caps) made of austenitic and austenitic–ferritic (duplex) stainless steel without specific inspection requirements. It specifies: - steel grades; - mechanical properties; - dimensions and tolerances; - requirements for inspection and testing; - inspection documents; - marking; - handling and packaging.