This European Standard specifies the tolerances on dimensions and form of round aluminium and aluminium alloys porthole extruded tubes with an outside diameter (OD) of over 2 mm up to and including 50 mm supplied in coil form or in straight lengths cut from coiled material: see Figure 1. This European Standard mainly applies to round extruded tube for general engineering applications manufactured in 1xxx series of aluminium and 3xxx series of alloys. The use of this European Standard for non-standardised 1xxx aluminium and 3xxx alloys or alloys from other series, e.g. 5xxx or 6xxx, is subject to agreement between supplier and purchaser. This European Standard only applies to: – round tube produced by the porthole/bridge method, extruded in coil form to the final dimensions required; – tube as above but delivered in straight lengths cut from coiled material. This European Standard does not apply to: – seamless extruded (die/mandrel method) tubes (EN 755-7); – tubes extruded in straight lengths (i.e. not coiled) (EN 755-8).