Are the square flap single lined envelopes gummed at the top so they can be sealed?

Yes, all of our single lined envelopes are gummed at the top so they can be sealed. Our single lined envelopes are offered in 3 sizes: 6 1/2 x 6 1/2 square, 5 1/4 x 7 1/4 (A7) & 5 1/2 x 8 1/2 (A9). 

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