What's the difference between A2, A6 and A7 envelopes?

Size. A2 (4 3/8" x 5 3/4") fits 4.25" x 5.5" cards, A6 (4 3/4" x 6 1/2") fits 4x6 photos and cards, and A7 (5 1/4" x 7 1/4") fits 5x7 invitations and cards.

Shop Custom A7 Envelopes (5 1/4″ x 7 1/4″) – 5×7 Invitation & Card Envelopes

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