Traders and financial professionals work at the opening bell on the floor of the New York Stock Exchange.

Check out the companies making headlines after the bell:

Shares of fitness clothing company Lululemon rose roughly 4% in extended trading following a strong first-quarter earnings report. The company reported earnings per share of 74 cents on $782 million in revenue, beating Refinitiv consensus estimates of 70 cents EPS and $755 million in revenue. The company also raised its full-year guidance for revenue. It expects revenue between $3.73 billion and $3.77 billion, and earnings per share between $4.51 and $4.58 in 2019."

Shares of RH, formerly known as Restoration Hardware, soared 22% after the company's first-quarter results beat expectations. The home furnishings company reported adjusted earnings of $1.85 per share on $598 million in revenue, surpassing consensus estimates of $1.55 per share on $584 million in revenue. RH also raised guidance the fiscal year and now expects adjusted revenue between $2.64 billion and $2.66 billion and adjusted earnings per share between $8.76 and $9.27.

Shares of cybersecurity firm CrowdStrike continued to rise after hours, following the stock's market debut Wednesday, when it rose by more than 70%. The stock gained as much as 1.5% after hours to trade around $58.89 per share after opening on the public markets at $63.50.