Our acid-free Bright Yellow matboards are 4-ply and feature a white core. With an overall size of 10x10, these mats with Circle openings fit perfectly into 10x10 frames and are bevel cut to showcase your 6x6 photos. Actual mat opening size is 5.5x5.5 inches so that it may safely and securely house your 6x6 photo, artwork, needlepoint, sign, etc. This pack includes 1 Single Matboard. Proudly made in the USA by Country Art House!