Do I need to apply any sealant before sliding this on?

Lap joint clamps work by mechanical compression alone — no sealant required. Ensure both pipe ends are clean and free of debris before installation for a tight fit.

Will this clamp work on existing exhaust or does the pipe need prep?

Your exhaust pipes should be clean and dry at the joint point. If the connection shows heavy rust or pitting, light surface cleaning is recommended to ensure full contact between the clamp and pipe.

What holds this in place once it's installed?

The lap joint design creates a mechanical fit — the overlapping sleeve compresses around both pipes and stays secured by friction and the pipe's own rigidity. It's designed to handle exhaust vibration without loosening over time.