both members of the lh54-425 binary system are hot, massive, and luminous stars. the less massive secondary has an effective surface temperature of 41,000 k and the more massive primary is 45,000 k. the stars are 8 and 11 times the size of the sun, and the combination of high temperature and large size means the primary star is 500,000 times as luminous as the sun and the secondary 160,000 times as luminous. they are emitting a stellar wind with a velocity of 2,800 km/s.