People ask me what is the purpose of the screw hole plugs, and why do I now sell 2 different kinds? Here is an example showing each plug and also an exposed screw head with no plug. By using the plug, you dont see any of the screws used to secure the new vinyl window. You can paint the screw head to match the white vinyl and it won't be as noticeable, but it will still be visible. By drilling a 3/8" hole into the first wall of vinyl, then installing the screw, and then inserting the plug into the 3/8" hole, no screw heads are showing. The differences  in the 2 different styles of plug are the wider plug has a little more detailed look where the small one is less noticeable. The larger plug has a longer insert that goes into the hole, and seems to go in easier than the narrow plug which uses tiny ridges that snap into the hole. You need to line the plug up just right in order for it to snap in place. In my experience, both plugs stay secure in the hole.

To learn more about Vinyl windows and doors, visit my website at http://www.how-to-install-windows.com