This product is a round, disc-shaped fuse that is glued to the side of cylinder heads and engine blocks to show if a cylinder head or engine block has been boiled by the owner after assembly.

For warranty protection and quality assurance reasons, we glue an overheating fuse to the cylinder heads we sell, which can be used to trace the history of the products at any time and to clearly determine if the engine has been operated in an overheated state.

A blown fuse indicates if a cylinder head has been used at an inappropriate temperature.

In good condition. Or the fuse of an engine that has been permanently above operating temperature: