Name
Small scale < 16 ESU*
Medium scale => 16 and < 40 ESU
Large scale => 40 ESU

(source: www.seamlessassociation.org)

*ESU: European Size Unit = 1200 euros standard gross margin (http://ec.europa.eu/eurostat/statistics-explained/index.php/Glossary:Standard_gross_margin_(SGM) )