Small devices and watertight enclosures in aluminium alloy suitable for applications in areas at risk of explosive atmospheres as defined in ATEX Directive 2014/34/EU. Back box and cover are treated with ecological anticorrosion passivation with fluoro-zirconium and finished with hot polymerized scratch-resistant non-toxic polyester painting. The cover is attached to the back box by means of stainless steel screws, while the sealing is guaranteed by a gasket in non-ageing elastomer. Predisposed for internal and external earth connection.