BAT99-116 (commonly called Melnick 34 or Mk34) is a binary Wolf–Rayet star near R136 in the 30 Doradus complex (also known as the Tarantula Nebula) in the Large Magellanic Cloud. Both parts are amongst the most massive and luminous stars known. It has a spectral type of WN5h and the most massive binary system with x-ray luminosity.