14k Phoenix all the way... Best bulb for 150w HQI. They are high output and look good.
Hook a ballast up to a kill-a-watt and see what kind of wattage that it pulls. It it pulls 185-190 watts, then it might be real m81. If it is right at 150, then it is a Chinese Knockoff or an electronic. All DE bulbs can be fired up on any ballast that are probe start, but they are not all the same wattage and will have different output.
Hook a ballast up to a kill-a-watt and see what kind of wattage that it pulls. It it pulls 185-190 watts, then it might be real m81. If it is right at 150, then it is a Chinese Knockoff or an electronic. All DE bulbs can be fired up on any ballast that are probe start, but they are not all the same wattage and will have different output.