I got two clips with an acid test kit. Both clips cracked within second of their first use and became functionless. Once the clip is cracked, it loses its ability to grip the paper. The clips are made of very cheap plastic and shouldn't be squeezed harder than you would squeeze while holding a worm between your fingers. I didn't know this at the time. I was very disappointed when the clips broke because I had to scramble to find another way to pull the paper out of the acid test without tainting the page.