Founded in 2012, Whoop is far from a household name in the world of fitness trackers. But over the years, the company has attracted its share of converts. It hasn’t had any issue attracting venture capital over the years, either. Last time we checked in on the Boston-based company was in late-2019, when it raised $55 million. Now it’s back with a massive $200 million raise.

The Series F round brings Whoop’s total funding to nearly $405 million — a pretty massive investment for a company of its size. The round, led by SoftBank’s Vision Fund 2, puts the valuation at a jaw-dropping $3.6 billion valuation.

Additional investors include IVP, Cavu Venture Partners, Thursday Ventures, GP Bullhound, Accomplice, NextView Ventures and Animal Capital. They join a long list of former backers, including the National Football League Players Association, Jack Dorsey and a number of professional athletes.

The company’s targeting of athletes marks a strong contrast with leading consumer wearables like the Apple Watch and Fitbit. In fact, the company has a specific offering for sports teams, as well as solutions for businesses, healthcare and government/defense.

Whoop’s name made the rounds recently when Fitbit announced a “Daily Readiness Score” for the Charge 5, which many likened to the company’s more advanced analytics.

The company cites “rapid growth” in its membership offering over the past year as a motivation behind seeking additional funding. That was likely driven, in part, by the decision in 2019 to make the $500 wearable free, while focusing on a subscription service that starts at $18 a month for an 18-month membership (the shorter the membership, the more the monthly fee).

Whoop is eying international expansion beyond the U.S. and using the massive influx of cash on R&D for its hardware, software and analytics solutions. Money will also go toward expanding headcount, which is currently in excess of 500 (with nearly half of those employees having joined in the past year).

“We are thrilled to deepen our partnership with SoftBank as we grow internationally,” founder and CEO Will Ahmed said in a release. “While we have experienced amazing growth in the past year, the potential of our technology and the vast market for health monitoring remains largely untapped.”