●Unit of measure : 1 set (10 envelopes and cardboard x 10 each) ●Mesatsubo: 2.8 oz (80 g) / Mail Frame: Hashi, Package Size: For A5, Not Regular ●Dimensions: 6 square envelopes: 6.4 inches (162 mm) x 9.0 inches (229 mm) + 1.2 inches (30 mm) flap: 6.1 inches (156 mm) x 8.6 inches (218 mm) / Case: 10.4 inches (265 mm) x 7.1 inches (16 mm) ●These envelopes are sized to hold A5 and 2L versions. A set of cardboard to prevent contents from breaking, so you can safely seal it in with confidence. Envelopes are made from quality cotton pulp blend that has a soft texture even in crisp, vibrant colors. We also pay attention to the material of the cardboard, and we use something that has a texture in the craft, so you can paste photos and write messages like a collage