The Kylie effect: Kylie Jenner’s $4 million ad for Australian designer Johansen

[Ulquiorra]

IT’S a pretty basic outfit ... a white, off-the-shoulder dress, teamed with over-the-knee boots.

The big difference? Kylie Jenner wore it.

The Keeping Up With the Kardashians star, 21, has delivered an Australian clothing label the most powerful endorsement possible on Instagram by wearing its designs.

Jenner - who is worth US$900 million ($A1.22 billion) - sported the $A349 jumper-dress by Byron Bay-based label Johansen in four posts, shot in a New York hotel room, and shared to her 114 million followers.

The garment - dubbed the “corset jumper dress” - has now sold out in size S/M on Johansen’s website since Jenner wore it (size M/L is still available).

The label believes Jenner’s posts amounted to $4 million worth of free advertising for the brand, which has gained global attention since the Kylie Cosmetics founder and Forbes cover star wore it.

“It has become industry knowledge that a product sponsored Instagram post published by the recently declared billionaire will set back any company approximately $1 million per photo,” Johansen designer Jessica Johansen-Bell said in a statement, published by The Northern Star.

“On Tuesday morning, Ms Johansen woke up to four photos uploaded by Kylie Jenner in one of Johansen’s Australian designed and made dresses to her ... followers.”

The items were sent to Jenner’s stylist by Johansen for her 21st birthday.

The “corset jumper dress” is described as having a “wide neckline, full length blouson sleeves with elasticated cuffs”, according to Johansen’s website.

It also features an “elasticated bottom hem waist line corset detailing with cotton laces pulled in to accentuate waist line or left loose for oversized fit”.

Jenner also wore another outfit from the same brand - the silk Cha dress ($290), which she shared on her Instagram story recently.

It’s the latest in a series of off-the-shoulder looks worn by Jenner, who has been on tour with her Astroworld rapper boyfriend, Travis Scott.

This is not the first time Jenner has worn an Australian brand.

Jenner and her sisters Khloe and Kourtney Kardashian have regularly sported popular Australian activewear label P.E Nation, even taking to their influential Instagram and Snapchat feeds to spruik the brand.

“We still high-five when we see the Kardashians (wearing the brand),” PE Nation designer Pip Edwards told News Corp Australia in February.

“They’re such a powerful family.”