These little guys are great and they're really small, they can be attached anywhere and they give you loads of extra batteries which is awesome. The price is right. They only have one mode, red and blue flash, but I only use them to personally see where my drone is when flying at night and just to draw a little attention since I'm in a city center bar Fly. area lot. I have a separate strobe on top for my FAA compliance, they are awesome, love them, I have them oriented so I can see which side of the drone I am looking at so I have two in the back and one in the front.