Sometimes the best-kept secrets are hidden in plain sight. Just ask Karen. Details: Designed by: Safely Endangered 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.