30 x 36 Blue Shrink Wrap Door Zipper Access Door CASE OF 6 Actual Dimensions of Opening: 24″ x 28″ Replaces Dr Shrink DS-36B Zipper doors provide easy access to areas under a shrink wrapped object. Opening and closing zipper doors is easier than zipping up a jacket. There s no issue of lining up the two halves of the zipper. The zippers on these doors are always connected even when the door is completely unzipped. Zipper doors are made from a material that looks similar to shrink wrap but is not meant to be shrunk or have heat applied to it. Heavy Duty By US Marine Products LLC