20 mm, to 25 mm miniatures. It is mostly used for historical gaming in part due to a wide selection of 1/72 scale models. Figures of 15 mm, 20 mm, 25 mm, 28 mm, 30 mm, 32 mm, and 35 mm are the most common for role-playing and table-top games. Smaller figures of 2 mm, 6 mm, 10 mm, 15 mm, and 20 mm are used for mass-combat wargames. Large sizes such as 40 mm and 54 mm were once popular with wargamers the in the past and are still used by painters and collectors. While the large miniatures have become popular again since the late 20th century, they are not as popular as the smaller sizes. In the table below, figure height alone (excluding base thickness) is the feature from which approximate scale is calculated. Scales smaller still are used when the game involves large vehicles (such as starships or battleships). For instance Axis & Allies Naval Miniatures: War at Sea uses 1:1800 scale, and scales down to 1:6000 are seen. There is no equivalent "mm" number for these scales as individual figures would be nearly microscopic and are not used as such in the games. Miniature figure scale chart The following chart provides a numerical relationship between model scale and multiple figurine scales based on the platonic idea of the height of a human being (humanoid). The meaning of 15 mm (for example) is therefore dependent on a defined reference height. Thus 15 mm in the context of a dwarven world where the reference humanoid is 60 inches tall, is not equivalent to 15 mm in the context an NBA model where the reference humanoid is 2 meter s tall. Both models can be described as 15 mm, but the real world sizes depend on the size of the reference humanoid. In practice, the reference humanoid is generally assumed to be the idea of the average height of the human male, within a 6-inch interval between 5.5 feet and 6.0 feet, unless otherwise indicated by the designer. Average human height is heavily dependent on the population measured within a geographical region and historical era. Painting Many role-playing gamers and wargamers paint their miniatures to differentiate characters or units on a gaming surface (terrain, battle mat, or unadorned table top). Fantasy, role-playing, miniatures, and wargaming conventions sometimes feature miniature painting competitions, such as Games Workshop's Golden Demon contest. There