This premium anti-static bag seals out both dust and moisture while controlling static electricity, is constructed with a durable single-track zipper that stands up to repeated use with side seam welding to prevent splitting, is amine-free, won't corrode polycarbonate and offers superior performance in low humidity. With a surface resistivity less than 1x1012 ohm/sq our 4 mil bags meet the full static decay requirements of MIL-PRF-81705E. Type ll and EIA-541. This can also be heat sealed, tied, stapled or taped shut.