This download is a ZIP file. To open a ZIP file on a PC, you will need a program like 7-Zip. You can download 7-ZIP free here. Once you have a zip program installed, click on the file icon and it should open. If it doesn’t, right-click on the file and choose “extract” and all of files should appear. On a MAC, all you need to do is click on the product ZIP file and a folder should appear with the PDF’s inside. If this doesn’t work, hold down the control key and click the product file icon. Choose “open with” and then select “archive utility.”