One of our most popular iron-on flag patches is the national flag of the United Kingdom, the Union Jack flag patch, in all-black thread! The United Kingdom blackjack flag patch and the black UK flag are popular around the world, and look great on biker vests and jackets. Measuring in at 3.5-inches by 1.75-inches, this British flag patch is an all-time favorite. Featuring highly detailed professional embroidery, this flag applique is perfect for display or even putting in a scrapbook.