The size is approximately 31 x 29 cm. The opening has a zipper, and I think it's light and easy to use. I bought it online, but it was larger than I expected, and I've kept it stored without using it. It's an unused item, but it has been stored at home, so please understand this before purchasing. I have several other items for sale. If you purchase multiple items, I can offer a discount. Please take a look if you'd like.