99.8% pure anhydrous (containing the least water possible and no denaturant) isopropyl alcohol is excellent for tape head cleaning, defluxing, stencil cleaning, other light cleaning, and as a flux thinner. Avoid "bargain" alcohols for critical electronic cleaning. Cheap alcohols contain much more water, which slows drying and can cause oxidation. Specs: Meets or exceeds TT-I-735 Rev. A, ASTM D770-05, and GE Aviation D5B57