Correction fluids are available at any office supply company or you can order them, by ones or by the case from Reliable.com a super office supply provider. You can also use finger nail polish with a _bright_ color. I use this for marking hand tools that have a left and a right hand operation like bending pliers. At a glance and without thinking I know which way is which, a rarity for me. Chalk I have used also but it wipes right off since I use the cheapest I can find, chalk without oils the hold them together. I like the stuff without the oils, the stuff that comes off and leaves a track everywhere. It is so much easier to get off the keys when I am finished marking them up. Newton
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