Christo Lube MCG129, 2 Ounces Preferred oxygen compatible lubricant by some regulators manufactures Recommended for use in static applications in open circuit diving systems More professionals use CHRISTO-LUBE oxygen compatible lubricants, which were designed specifically for open and closed circuit diving systems. Perfect for all SCUBA o-rings CHRISTO-LUBE oxygen compatible lubricants are chemically as well as biologically inert, non-toxic, non-flammable and have no fire or flash point which results in them being the safest lubricants for use in oxygenated environments.