I have purchased from bob lasers before, their products are not that good. I had purchased 10x100mW. Turns out they are all in the range of 50-55mW. Very dissapointed. This was used with a thoram optics measurer which cost me $1200 when i purchased it. I tried to refund and they were having none of it, saying 'we test product, all good'. Luckily i was able to sell them on at a small loss. Tip: AVOID