A decent level actually. I use it on my GoPro mountain bike camera when the camera is mounted on the head tube. This gives me a quick vertical frame of reference. Because my camera is so small, I had to cut one of the bubble level parts out of the holder part. The bladder part survived the Dremel operation and then I glued it to the camera body. Has been working for several weeks now. Paid 5.53 and shipping was free. Purchased directly from Revain on 01/24/2011.