Check out the companies making headlines after hours.

NextEra Energy — Shares fell 3% in extended trading after the company announced its intent to sell $2 billion in equity units. Each equity unit will be issued in the amount of $50 and will consist of a contract to purchase NextEra Energy common stock in the future, as well as a 5% undivided beneficial ownership interest in a NextEra Energy Capital Holdings debenture due Sept. 1, 2027, issued in the principal amount of $1,000.

Danaher — The medical company saw shares rise 4% after announcing plans to spin off its environmental and applied solutions business to create an independent, publicly traded company. It also raised its third-quarter revenue guidance, according to FactSet.

Rhythm Pharmaceuticals — Shares of Rhythm Pharmaceuticals fell about 11% after the company announced a $100 million stock offering.

Arconic Corp — The manufacturing company's shares slid about 8% after Arconic provided a lower-than-previously-expected revenue forecast for the full year, citing the impact of operational issues and the combination of demand declines and higher unhedged energy costs in Europe.