Clear polypropylene film has a strong adhesive that withstands repeated temperature cycles without lifting. Non-pierceable. One pre-cut strips seals two rows of eight wells or 0.2 ml tubes and measures 19.0 x 97.3 mm, including the two removable tabs. (76.2 mm long without tabs.) Certified RNase, DNase, and nucleic-acid free. One box holds 50 sheets of 4 (200) strips.