Peacocks have always fascinated us. To attract a lady, called a peahen, peacocks fan their long, ornamented and colorful tail feathers and by shaking them, they emit a low-frequency sound, which peahens can hear, but us humans cannot. The brilliance of the peacock’s feathers comes from an optical phenomenon, called iridescence, the same trick hummingbirds use to make their neck-feathers shine. Differently spaced small crystal-like structures in their feathers reflect light by changing its wave length, thus accentuating certain colors over others and creating these amazing vivid fluorescent colors and ornamental effects. Title on the back of the card: Peacock Inside Message: No message. The inside is blank. QR-code: The QR-code provides the recipient of your card a link to background information about the image on the front. Guide: Reading QR-codes with your smartphone. Size: Image: 4" x 6", hand-trimmed. Card: 5" x 6 ⅞" Envelope: 5 ¼" x 7 ¼" Each card is individually wrapped in a protective sleeve with its envelope. Material: Card: acid free paper, front side is embossed. Image: printed on archival grade Professional Endura Premier Color Paper from Kodak with a silk surface finish. Fingerprint and smudge resistant. Made in the U.S.A.