Our acid-free Mid Grey matboards are 4-ply and feature a white core. With an overall size of 12x16, these mats with Oval openings fit perfectly into 12x16 frames and are bevel cut to showcase your 8.5x11 photos. Actual mat opening size is 8x10.5 inches so that it may safely and securely house your 8.5x11 photo, artwork, needlepoint, sign, etc. This pack includes 1 Single Matboard. Proudly made in the USA by Country Art House!