Kate Middleton
Kate Middleton uses this insole to wear heels all day. Pictured: Middleton opens an Action on Addiction Community Treatment Centre on Feb. 7, 2018 in Wickford, United Kingdom. Getty Images/Eddie Mulholland

Kate Middleton has a secret as to why she can endure wearing heels all day.

Whenever the Duchess of Cambridge attends royal engagements, she mostly prefers to wear heels. Most women dread the thought of wearing heels all day, but Middleton seems to have a way to make this bearable. According to Town & Country, Prince William's wife uses Alice Bow's leather insoles. The product offers comfort to help women enjoy their footwear.

Bow, the founder, confessed that she has a lot of shoes, but don't find them comfortable. This is why she created her product to create a solution to "ugly or ineffective insoles."

Bow studied shoemaking and spent six months testing prototypes. Her insoles are made of slim but effective padding topped with gorgeous soft leather in a stunning range of colors. The insoles can be personalized if the customers want it. Bow offers 5 pairs for only $178.41, but each pair costs $24.89.

In related news, Middleton opened a new addiction treatment center in Wickford on Wednesday. The Duchess arrived at the event in a bright blue coat from Goat and paired it with black stilettos.

Middleton's heel got caught in a grate. Fortunately, the seven months pregnant royal was able to maintain her balance and avoid toppling over. The mother-of-two just laughed off the mishap and continued greeting the staff.

For the said event, Middleton met Vice Lord Lieutenant of Essex Jonathan Douglas-Hughes who stumbled himself when he met the Duke and Duchess of Cambridge in 2016. "I reminded her [about the fall]. My wife told her that she would ensure I didn't do it again. Then she caught her heel. She said, Oh…do the same as you!" Douglas-Hughes told the reporters.

Aside from wearing heels, Middleton is a fan of wedges. In fact, she has been seen in this footwear on multiple occasions already. But the Duchess does not wear this type of shoes whenever she is with the queen.

"The Queen isn't a fan of wedged shoe," a source said. "She really doesn't like them and it's well known among the women in the family."

Meghan Markle is expected to abide by the same rules. But some will not be surprised if she wears one when she's with Queen Elizabeth II because Prince Harry's fiancée has been breaking the royal protocols.