The new specification is known as MIL-PRF-63460F or NATO S-758. The weapons lubricant is commonly known as CLP. Type “A” is for “traditional” CLP and Type “B” is for “bio-based” CLP Please be advised that existing NSNs are the same for the MIL-PRF-63460D specification and the MIL-PRF-63460F specification. Please note that lubricants that qualified under 63460D or earlier are no longer valid and do not meet the criteria of the new 63460F specification. To prevent using lubricants that are no longer approved, Military organizations should be especially cautious and take note when purchasing.