Celebrate a birthday with a big loud HIP HIP HOORAY! The only acceptable way to greet people on their birthday. Details: Designed by: Kong-Yew Wong. Size: A6 (105 x 148mm / 4.1 x 5.8 inches). - that fits as a standard sized letter in the UK mail. Produced from sustainable forests and/or recycled materials. Blank inside for your own message. 100% recycled brown kraft envelope supplied. Made in the UK.