This product is awarded patent by the China government already in 2007. Its four edges can be opened easily, and a photo or file can be inserted very conveniently, then just cover the edges again. You do not have to use any screwdriver when inserting or taking out the photo or file.
We have six sizes of this product: A0, A1, A2, A3, A4 and A5. Their outer sizes are as follows:
A0: 1223 x 875mm
A1: 875 x 628mm
A2: 628 x 454mm
A3: 454 x 331mm
A4: 331 x 244mm
A5: 244 x 182mm
Here we just quote A4. Prices of other sizes are available upon request.