Sweetness of wine or the slightly sweeter classification of "Brut" or even "Extra Dry/Extra Sec/Extra Seco" (because 9 + 3 = 12 grams per litre). The rules applicable to labellings before 14 July 2009 were: In Austria, the Klosterneuburger Mostwaage (KMW) scale is used. The scale is divided into Klosterneuburger Zuckergrade (°KMW), and very similar to the Oechsle scale (1 °KMW =~ 5 °Oe). However, the KMW measures the exact sugar content of the must. In Canada, the wine industry measures wine sweetness as grams of sucrose in 100 grams of grape juice or grape must at 20 °C in degrees Brix. In
Brix prism; the result is observed through an eyepiece. The critical angle (the angle beyond which light is totally reflected back into the sample) is a function of the refractive index and the operator detects this critical angle by noting where a dark-bright boundary falls on an engraved scale. The scale can be calibrated in Brix or refractive index. Often the prism mount contains a thermometer which can be used to correct to 20 °C in situations where measurement cannot be made at exactly that temperature. These instruments are available in bench and handheld versions. Digital refractometers also find the critical