同時貼有圖案內容相似或相關的郵票和火花,經蓋銷實寄的信封.因郵票又稱“郵花”,故謂之“雙花”或“姊妹花”。由於郵票和火花票幅相近,內容題材多有共同之處,因此一些既收集郵票又收集火花的愛好者便將二者結合起來,製作出具有異趣的收藏品.雙花封要求雙花之間儘可能達到一致,並且並排貼上用同一郵戳蓋銷,因此一枚製作較完美的雙花封,也是一枚難得的趣味品.At the same time posted with patterns similar to or related stamps and sparks really send the envelope through the cancellation. Due to postage stamps also known as "Post Flowers", so that the "double flower" or "sisters." As stamps and sparks ticket sites are similar, the content of many subjects in common, so the collection of stamps that are both fans of Bianqiang spark is collected combining to produce a different interesting collectibles. Shuang-Hua Feng requirements between pairs of flowers as much as possible to reach consensus, and with the same postmark affixed side by side, it produced a more perfect pairs of flower closure, but also a rare taste of products.