If he is wheely really the best dad ever then let the old man know just how much he means to you! Details: Designed by Kong-Yew Wong. Size: Square (148 x 148mm / 5.8 x 5.8 inches). - that fits as a standard sized letter in the UK mail. Produced from sustainable sources and/or recycled materials Blank inside for your own message. 100% recycled brown kraft envelope supplied. Made in the UK.