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Professional strength fast acting resealer, stops leaks fast
Rejuivinates all rubber seals & gaskets in engines, transmissions, power steering, differentials and hydraulic systems
Compatible with conventional and synthetic oils, ATF, gear oil, power steering fluids and hydraulic oil
Does not contain petroleum distillates, will not over-swell or breakdown seals
8oz bottle will treat a 6 quart capacity, adjust accordingly

From the manufacturer

AT-205 Re-Seal - How it works

AT-205 added to leaking system

AT-205 Re-Seal is added to any leaking engine, transmission, power steering system, differential or hydraulic system (except for brakes) to condition rubber seals/gaskets and stop leaks. Simply pour it in as you would be filling it with oil or fluid.

The formulation blends with the oil

The additive blends with oil in the system and is circulated throughout during operation, treating and conditioning rubber seals and gaskets.

Conditions and rejuvenates seals

AT-205 is a plasticizer, a type of chemical used in rubber manufacturing to set hardness and flexibility. As a seal or gasket gets older it can dry out, harden and wear - treating it with AT-205 will rejuvenate it, restoring it's flexibility and sealing properties.

Most leaks resealed within 5 hours

As long as the seal or gasket is not severely damaged or torn, the leak is resealed after a total of 5 hours of driving - saving time and money from costly repairs.