Loctite Copper Anti-Seize Lubricant Brush-Top 8 oz — High-Temp Protection to 1800°F, Conductive

Loctite 38650 Copper Anti-Seize Lubricant is an 8 oz. brush-top compound formulated to prevent seizing, corrosion and galling on threaded and metal surfaces exposed to high temperatures.

This copper-based anti-seize paste is engineered for automotive and industrial use where metal-to-metal contact faces extreme heat, pressure or corrosive environments. It maintains good electrical conductivity, spreads easily with the integrated brush, and withstands a broad operating range from -30°F up to 1800°F. Typical uses include spark plug threads in aluminum cylinder heads, exhaust manifold bolts, engine hardware, sensors, thermostat housings and battery cable connections.

How does Loctite 38650 protect threads at high temperatures?

The copper particles in the paste form a barrier between mating metal surfaces so parts can be disassembled after exposure to heat. Its formulation resists breakdown and oxidation at elevated temperatures, reducing the risk of threads welding or galling.

• Service range up to 1800°F for high-heat applications
• Copper solids provide durable metal-to-metal separation
• Prevents bolt and stud seizure from heat and corrosion

Can I use this on electrical connections and sensors?

Yes — Loctite 38650 offers good electrical conductivity, making it suitable for select electrical and sensor terminals where a conductive anti-seize is required. Apply sparingly and avoid contaminating sensor faces or insulated areas that must remain non-conductive.

• Suitable for battery cable connections and sensor threads
• Helps maintain conductivity while preventing corrosion
• Not for use where insulation or dielectric isolation is needed

What is the best way to apply the brush-top 8 oz. container?

The brush-top cap delivers controlled, mess-reducing application directly to threads and contact points. Clean surfaces of grease, dirt and old compounds first; then twist open, brush a thin, even coat onto threads or mating surfaces before assembly.

• Integrated brush for accurate placement and less waste
• Apply a thin film — excessive paste can attract debris
• Wipe cap and tool after use to keep the container clean

Will this work on aluminum and stainless fasteners?

Loctite 38650 is commonly used where dissimilar metals meet, such as steel bolts in aluminum heads, to prevent galvanic corrosion and thread seizure. It also performs well on stainless steel, helping avoid galling during torque and removal.

• Ideal for spark plugs in aluminum cylinder heads
• Reduces galvanic corrosion between dissimilar metals
• Protects stainless fasteners from galling under load

Who is this for: Loctite 38650 Copper Anti-Seize Lubricant is aimed at professional mechanics, DIY automotive enthusiasts and industrial maintenance teams who need reliable high-temperature thread protection and electrical conductivity. Choose this brush-top 8 oz. size when you want precise application, fewer drips, and a product suited to engine parts, exhaust components, sensors and battery connections where future disassembly is likely.