Pint glass small pits which aid in nucleation, allowing the gas within it to be released more easily, thus preserving the head. Without the aid of these pits a regular pint glass will keep a head for only 3 or 4 minutes before appearing 'flat'. The markings come in a variety of styles ranging from a simple circular or square hatched pattern to more complicated branding messages. Pint glass collecting is an increasingly popular way for individuals to commemorate their visits to popular tourist destinations, most notably to microbreweries or sports arenas. These destinations often sell pint glasses adorned with their logos,
Pint glass present, the capacity line. There are no legally prescribed sizes for beer volumes, but the stated capacities, which are a legal requirement, must be formally tested by the hotelliers and breweries. In Canada, Federal law mandates a standard imperial pint. However, this law is rarely enforced, and establishments typically sell US pints or other measures as "pints." The Republic of Ireland uses the imperial 20 fl oz pint measure (≈568 ml), where legal metrology marks are used to show that a glass has passed inspection by the National Standards Authority of Ireland, a state-run body which enforces a number of