Our acid-free Mid Grey matboards are 4-ply and feature a white core. With an overall size of 10x13, these mats with Oval openings fit perfectly into 10x13 frames and are bevel cut to showcase your 8x10 photos. Actual mat opening size is 7.5x9.5 inches so that it may safely and securely house your 8x10 photo, artwork, needlepoint, sign, etc. This pack includes 25 Matboard Show Kits With Acid Free Backings & Clear Bags. Proudly made in the USA by Country Art House!