MIL-S-8660C Silicone Lubricating Compound

PST-525 is a light-bodied, MIL-S-8660C compliant, QPL listed, moisture proofing, silicone compound for mechanical and electrical connections. This product was formerly known as SSP-1401-L and is now a PolySi® G-MAN® silicone lubricating compound.

Data Typical Values
Appearance White/Transparent
Temperature −70°F to 400°F
Worked Penetration 275
Unworked Penetration 230
Bleed (30 hrs. @ 204°C) 2%
Evaporation 1%
Specific Gravity 1.01

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MIL-S-8660C Silicone Lubricating Compound

PST-525 is a silicone lubricating compound that meets the requirements of the MIL-S-8660C specification and is part of the U.S. government’s Qualified Products List (QPL). This light-bodied silicone compound is comparable to Dow Corning 4 electrical insulating compound (DC-4) and to Novagard G624 dielectric silicone grease.

PST-525 Silicone Grease Features

PST-525 silicone grease has an operating temperature range of −70°F to 400°F and an unworked penetration in the 200 to 260 range with a typical value of 230. This silicone lubricating compound is moisture-proof and water repellent, electrically insulating, non-corrosive, and low in volatility. PST-525 also has excellent thermal and chemical stability properties.

PST-525 Silicone Grease Applications

PST-507 silicone lubricating grease is used in applications that require conformance and certification to MIL-S-86660C requirements for non-melting, heat-stable silicone compounds. Moisture proofing, electrical insulation, and mechanical lubrication applications include:

  • electrical connections
  • ignition systems
  • electronics components
  • threaded connectors
  • plastic and rubber parts
  • door seals
  • battery terminals

PST-525 Packaging and Product Specifications

PST-525 silicone lubricating grease is supplied in drums, plastic pails, jars, cartridges, and tubes. Private labeling and custom packaging are available to meet special requirements. Contact PolySi Technologies for more information.