Which of your products should I use to protect the inside of my arches against salt etc?

Our wax-based anticorrosives are best for this.

If the arches have liners remove them and clean out any mud or debris then apply Dynax-S50. On areas not covered by liner use Dynax-UB. This is a firmer film, however it will need top ups as it slowly wears from the surface by discharge from the wheels. Top up is quick and easy with the 750ml aerosol and will preserve the arches perfectly.