Our acid-free Dill Green matboards are 4-ply and feature a white core. With an overall size of 18x18, these mats with Circle openings fit perfectly into 18x18 frames and are bevel cut to showcase your 14x14 photos. Actual mat opening size is 13.5x13.5 inches so that it may safely and securely house your 14x14 photo, artwork, needlepoint, sign, etc. This pack includes 1 Single Matboard. Proudly made in the USA by Country Art House!