The openings are 2.25" x 3.25". Openings all have a white bevel. Colors we have in stock are in the third picture. They are from left to right: Brite White, Light Grey, Medium Grey, Soft white, Pink, Cream, Red, True Green, Spring Green, Forrest Green, Silver Blue, Royal, Sky Blue, Navy, Brown , Tan, Chaarcoal, Gold, Silver Black Yellow not shown. Fabric matting is also available for a small additional cost. See our shop for other style mats and frames. Other Sizes are also available Fabric matting is also available for a custom order. We can also do custom sizes for openings and frame size. Other fancy shaped openings such as oval, rectangular or cove are also possibilities. Just let us know what you would like. CHOOSING THE CORRECT MAT SIZE When purchasing a mat for a picture frame be aware that your standard frame should measure at least 1/8” larger than the size of the mat you purchase. In other words an 11 x 14” frame should actually measure at least 11 1/8” x 14 1/8”. You mat will measure 11 x 14”. In addition there is a 1/16” allowance on the mat so it can measure 10 15/16” x 13 15/16” up to 11 1/16” up to 14 1/16” and still fit in your standard frame. The mats are custom cut one by one so not returnalble but if you have a problem let us know and we will work with you to resolve.