SET of 10 - GREATPACK 16x20 White Single Mats- Fit 11x14 Photo Art This is a set of ten 16x20 single white mats with beveled cut openings and matboard backing for each. The opening size is 10.5" x 13.5" to fit 11"x14" image sized photos or art. These are acid free neutral ph mats with a white core which does not yellow over time like many regular core mats available. These same high quality 10-packs available as both single and double mats in 5x7, 8x10, 9x12, 11x14, 12x16 and 16x20 sizes in white, antique white and black.