Actually I want to buy MP3 Sunglasses that have 5mW + 5mW (320hm) output, but I don't know what that means. I know that 5 mW is 5 megawatts, but I don't know what's 320hm, and is this good.
A silvery brook comes stealing From the shadow of its trees, Where slender herbs of the forest stoop Before the entering breeze. WILLIAM CULLEN BRYANT: _The Unknown Way._
As you expected correctly, mW is short for megawatts. 320hm either means 'Ohm', which should be 23 kg*m² / V²s³ or that you're a bot, trying to trick us into klicking the link you posted at the end of your brabbling.