The term is often applied to both types of concrete mix used for swimming pool construction, i.e. dry mix shotcrete and wet mix shotcrete. According to the American Concrete Institute, it should only be applied to dry mix shotcrete since this is the historic derivation of the term and the only one of the two types applied under high pressure where the material moves through one hose and is mixed with water, also under high pressure, from another hose, these coming together at the nozzle or gun, hence the term "gunite". The mix is sand, cement, water and sometimes a bonding material. This is the process used in Omega's pool construction.