Twenty one or 21 – a triangular number, expressed here on this different personalised birthday card for a 21st Birthday.
Numbers, eh? Well, for your twenty-one-today year-old they might like to know that 21 is a triangular number (not that they’ll care much) but at least you can impress them with a card that’s a little different from the norm and will allow you to remind them that although they are now an adult, you’re still smarter than them.
All our Cards are printed on 100% recycled, sustainable stock.
We print our cards on heavyweight recycled card, supplied by a family-run papermill in the UK. Please recycle your card!
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Sizes & Stock.
Our cards are all 5×7 inches (127mm x 177mm) when folded. They are printed on 300gsm uncoated recycled card stock and can be recycled again.
Delivery times are 3-5 days from the date of order (payment received). Please note that we don’t currently offer express delivery. All items are delivered by Royal Mail.
Our cards are supplied with coloured envelopes to match the colour of your card’s design. For certain products, you can choose your envelope colour.
We post all our cards in board-backed envelopes to keep them safe. We can also pack your card in protective cellophane, but not doing so saves on plastic waste – all cards have the option to ship with or without additional plastic packaging.