本规范涵盖用于主汽轮机和辅助汽轮机、齿轮、空气压缩机和某些液压设备以及一般机械润滑的合成汽轮机、液压和齿轮润滑油的单一分类，中等用途。由于其合成基础油，在目前使用MIL-PRF-17331（2190 TEP）且需要长期使用寿命和/或氧化稳定性的某些应用中，这种油可以提供更好的性能，例如在高压空气压缩机（HPAC）中。

This specification covers a single classification of synthetic steam turbine, hydraulic, and gear lubricating oil, moderate service, for use in main and auxiliary turbines, gears, air compressors, and certain hydraulic equipment, as well as for general mechanical lubrication. Due to its synthetic basestock, this oil could offer improved performance in certain applications currently utilizing MIL-PRF-17331 (2190 TEP) where long-term operational life and/or oxidative stability is desired, such as in High Pressure Air Compressors (HPACs).