The Pool Mixed Envelopes are part of the Hero Hues Collection by Hero Arts. Included are four each of three colors (pool, tide and shallows) that are archival and acid free. These envelopes have color on the outside and are white on the inside. Included in this set are 12 A2 envelopes that measure 5.75" x 4.5". Made for use with Pool Mixed Folded Cards (hro-ps639, sold separately).