If you already have corroded-in fluid cover screw that's partially stripped by Phillips screwdriver, even proper JIS bit may not fit properly to remove. In that case, hammer-operated impact screwdriver will work. I've used this on screw-heads that were completely rounded off! Be sure to test impact direction by pushing tip gently on hard surface to make sure it spins in loosening direction.
6 Bit Impact Screwdriver Set With Case
Amazing deals on this 6Bit Impact Screwdriver Set W/Case at Harbor Freight. Quality tools & low prices.
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