Christo Lube MCG 111 - 5 Gram tube Meets the specification requirements and has been qualified under Military Specification MIL-PRF-27617F Types I, II and III. Has been adopted as the preferred oxygen compatible or enriched air (Nitrox) lubricant by most breathing apparatus equipment manufacturers. Has been tested and approved by NASA for use in liquid and gaseous oxygen (LOX/GOX) systems up to 10,000psi. More professionals use CHRISTO-LUBE oxygen compatible lubricants, which were designed specifically for open and closed circuit diving systems. 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.