The Nipper, which Princess Kate had made in navy, is said to be perfect for jogging and off-road walks in the countryside
Credit: Max Mumby/Indigo/Getty

When it comes to traveling in style and comfort, Prince George and Princess Charlotte have had a selection of strollers (from heritage royal heirlooms passed down from the Queen to state-of-the-art modern designs) at their disposal.

Now, the latest model, called the Nipper, produced by U.K brand Out ‘n’ About, has been given the royal seal of approval – and the company couldn’t be more thrilled.

“There has been a surge in orders and we have sold out of a lot of stock,” Marie David, marketing manager at the firm, tells PEOPLE. “We are just a small, family run business, so it is very exciting!”

The original inquiry was placed by George’s grandmother, Carole Middleton via the Bedfordshire-based firm’s website when the prince was just 18 months old.

“She said her neighbor in Bucklebury had recommended the buggy to her for her grandson as it s a good all-terrain style, David continues.

Ever the practical mom, Princess Kate really wanted the buggy in navy, a color that had been discontinued.

“The new vibrant colors weren t quite what they were looking for, so we said we may still have some of the old fabrics left – and we did!” David adds.

Established 15 years ago for parents leading an active lifestyle, the buggies have become a cult favorite with sporty moms in the countryside, and it was their all-terrain versatility that appealed to the royal mom.

“They had heard how good it is, off-road, for long walks and that kind of thing. Our buggies are well known for those features, David adds.

Made from the discontinued navy fabric, upholstered onto an updated current frame, the model is a complete one-off.

“It’s a bespoke buggy and it’s not actually available on the market currently,” confirms David, who adds that Princess Kate paid the full price of $382 on delivery to Kensington Palace. Soon after Charlotte’s birth, they had another order for a matching bespoke navy carry cot ($172), which is generally used from birth to six-months.

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It’s not the first time that Kate has requested bespoke features on one of George’s strollers. In 2013, the royal mom contacted the British heritage brand Silver Cross and requested some bespoke accessories for her Sleepover Elegance, also in navy. As a result, items such as an insect net, requested by Kate, were rolled out to all customers.

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The Nipper Single, which features a 360-degree swivel front wheel and a robust lightweight aluminium frame, was last spotted when Kate and Prince William took their children on a day out with friends to the local horse trials in Norfolk.

“To know they are using it and enjoying is great,” says David, who says she recently got a request for “spare inner tubes and tires from the couple’s personal assistant – another sign that the buggy is well-loved and likely to be used by little sister, Charlotte.