RNase-free, hydrophobic covers are lighter weight than glass. Polycarbonate plastic cover slides are ready to use without washing or siliconization. Hydrophobic working surfaces are protected with clean release liners to prevent RNase contamination. The plastic cover slides remain flat and will not curl, even at high temperatures. Plastic cover slides do not chip, crack, or break and are dust-free. Square cover slides are supplied protected in a sandwich polyethylene film. The circle cover slides are packed between fiber-free paper slips. Use Dow Corning® Vacuum Grease (HR3-510), Dow Corning® 7 Release Compound (HR3-508), or immersion oil to seal cover slide to plate.