Arctic Hayes Gas Leak Detector Fluid has been specially formulated to trace positive pressure leaks in pipelines and fittings. It has a non-flammable and non-corrosive formula, suitable for use on gas, air and nitrogen leaks. The micro-porous foam instantly highlights the smallest of leaks, safe to use in confined areas. There is a brush-on applicator in bottle cap. Meets requirements of BS EN 14921:2004.