This is high test stuff we use in a low-test situation (short-travel piston, a few thousand cycles). I understand they're all grade 2, unless special ordered.I happen to have picked up an 8 ounce tub of 225 on Ebay for cheap.
Here are some grease descriptions:
The Krytox™ GPL 21X series contains molybdenum disulfide for extreme pressure (EP) conditions and should be used for slow speed or extremely heavily loaded applications.
The Krytox™ GPL 22X series contains sodium nitrite corrosion/anti-wear inhibitor; it also improves load-carrying performance and is ideal for corrosive environments. Typical
applications are automotive bearings, sealed pump bearings, electric motor bearings and general-purpose bearings.
The Krytox™ GPL 29X greases have extreme pressure (EP) and anticorrosion additives and have been formulated for applications that need both high load-carrying capacity and
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