26240 Permatex Permanent Strength Threadlocker RED and Cup/Core Plug Sealant Retaining Compound

Permatex 26240 is a permanent-strength threadlocker and cup/core plug sealant compound that serves a dual purpose on the bench. Applied to fasteners ranging from 3/8 in. to 1 in. (10 mm to 25 mm) before assembly, it resists heavy shock, vibration, and extreme chemical or environmental conditions. The same compound seals and secures cylindrical metal assemblies, making it a practical choice for engine cup plugs and core plugs. Separation requires localized heating and hand tools. The product conforms to ASTM D5363 AN0331 (Mil-S-46163A, Type II, Grade O). Call us to confirm proper fit for your application.

Features

Dual-purpose formula: threadlocks fasteners AND seals cylindrical metal assemblies
Designed for fastener sizes 3/8 in. to 1 in. (10 mm to 25 mm)
Permanent, high-strength hold resists heavy shock, vibration, and extreme chemical or environmental conditions
Conforms to ASTM D5363 AN0331 (Mil-S-46163A, Type II, Grade O)
Separation requires localized heating and hand tools

Tech Specs

• Fastener size range: 3/8 in. to 1 in. (10 mm to 25 mm)
• Strength level: Permanent, high-strength
• Color: Red
• Application: Threadlocking and cylindrical metal assembly sealing
• Specification compliance: ASTM D5363 AN0331 (Mil-S-46163A, Type II, Grade O)

Additional Information

Permatex 26240 is a dual-purpose compound. As a threadlocker, it is applied to fasteners 3/8 in. to 1 in. (10 mm to 25 mm) before assembly to resist heavy shock, vibration, and extreme chemical or environmental conditions. As a retaining compound, it seals and secures cylindrical metal assemblies such as cup plugs and core plugs. Once cured, localized heating and hand tools are required to separate assembled parts. Conforms to ASTM D5363 AN0331 (Mil-S-46163A, Type II, Grade O).