Oxidized Switch Contacts - Test Equipment

My company uses several pieces of fairly old (10-20 years) electronic test equipment, in perfectly good working order, except for some poor contacts in switches. Some of the contacts are buried in switches that cannot be easily disassembled, so the cleaner would need to be an aerosol.

Please recommend your absolute best contact cleaner (regardless of it's price) to clean dirt, oils, and oxidation from the switch contacts.

Also, I have used WD40 in the past, with reasonable results, but I would like to flush it out before applying your recommended cleaner. What is your recommendation for flushing out WD40 as well?

S. Richards
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We reommend using the DeoxIT® (D5S-6) a few times to remove the WD-40, then finish with a couple bursts of DeoxIT®. It is, by the way, modestly priced.