Hair products maker Olaplex Holdings Inc fetched a valuation of more than $13.6 billion in an upsized initial public offering after pricing shares at $21 apiece, the Advent International-owned company said on Thursday. Since its founding in 1984, Advent has made 390 private equity investments in 42 countries totaling $56 billion.

Olaplex, a Santa Barbara, California-based hair care company, said selling stockholders offered 73.7 million shares, raising about $1.55 billion. They had earlier planned to sell 67 million shares in the price range between $17 and $19 each.

Olaplex's offering comes as Americans, over the past year, spent more on skin and hair care products compared to make-up and cosmetics due to the COVID-19 pandemic and its associated lockdowns.

The company sells shampoos, conditioners, treatments and oils aimed at treating damaged hair, with prices running up to as much as $196 for a bundle.

Its net sales grew 90% year-over-year in 2020, a recent regulatory filing showed, while adjusted net income rose to $131.1 million over the same period from $100.5 million a year earlier.

Founded in 2014 in a California garage, Olaplex sells its products in more than 100 countries, with beauty chain Sephora and SalonCentric and Sally Beauty Holding Inc's Beauty Systems Group among its biggest customers.

Advent, which bought Olaplex in 2019, owns about 79.6% of the combined voting power in the company after the offering through associated investment funds.

Olaplex shares are expected to begin trading on the Nasdaq later on Thursday under the symbol "OLPX," and the offering is expected to close on Oct. 4.

Goldman Sachs & Co, J.P. Morgan, Morgan Stanley and Barclays were the lead underwriters for the IPO.