Camphor produces fumes that form a coating on the tools that prevents rust.

What can I put in my toolbox to prevent rust?

There’s an easy solution, though: Once you’ve finished cleaning and shining them, simply drop a few pieces of chalk in your toolbox to help keep moisture to a minimum. Less moisture will mean less worry over rust.

What is a good rust inhibitor?

From the makers of the world’s most famous rust-penetrating lubricant comes WD-40 Specialist Long Term Corrosion Inhibitor. The makers of WD-40 know a thing or two about dealing with rust and this product features a special formulation variant to help keep that rust from forming or spreading.