The most common international unit for the MVTR is g/m²/day. In the USA, g/100in²/day is also in use, which is 0.064516 (approximately 1/15) of the value of g/m²/day units. Typical rates in aluminium foil laminates may be as low as 0.001 g/m²/day, whereas the rate in fabrics can measure up to several thousand g/m²/day.