HP Advanced Photo Paper resists water, smears and smudges. Good choice for printing in humid environments. Sturdy, glossy, and even water-resistant photo paper dries instantly for quick photo handling, passing around and stacking. Get true-to-life color photos without the guesswork. HP Auto Sense technology makes it easy to print fast, vivid color photos by automatically selecting the optimal print settings of select HP printers. Lignin-free, calcium-carbonate free. 10.5 mil thickness.