According to the EU regulation, the nominal volume of wine of all quality classes is expressed in hectolitres (hl), litres (l), centilitres (cl) or millilitres (ml). Differently for still and sparkling wine, the volumes listed below are permitted on the bottle label in litres, whereby an "e" (code for calibrated bottle) must be added. Still wine: 0.1 - 0.187 (for airplanes, ships, trains or duty-free shops) - 0.25 - 0.5 - 0.75 - 1 - 1.5 - 2 - 3 - 4 - 5 - 6 - (7 explicitly not) - 8 - 9 - 10. Sparkling wine: 0.125 - 0.20 - 0.375 - 0.75 - 1.5 - 3 - 4.5 - 6 - 9. According to the EU packaging regulation, the volume must be "sufficiently constant". Deviations of up to 6% from the actual bottle contents are tolerated. In Austria, the nominal volume must also be included on the banderole. See also under barrel types, bottles and hollow dimensions.
For me, Lexicon from wein.plus is the most comprehensive and best source of information about wine currently available.Egon Mark
Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)