The EnvyPak four pocket page is an acid-free archival quality page perfect for storing standard sized Polaroid Instant Photos. These pages are 100% made in the USA from USA raw materials. Great for collectors, presenters, and hobbyists. These polypropylene page protectors offer crystal-clear protection for individual items and these pages contain no vinyl. A premium look and feel at an economical price. We use 3.5 mil polypropylene to make these so they are considered to be heavyweight or heavy-duty grade of sheet protector. The pages are three hole punched and will fit all standard three ring binders.