this is great for small blocks and stuff but if the pipe you are clearing connected to another line you might cause a bigger problem. Our kitchen and laundry room pipes are connected and stopped up, further down the line our bathroom comes in and than the toilet. We plungged the line so much we pushed the stop all the way to the bathroom so we couldn't do anything in the bathroom but go to the toilet. We stopped there. It took 4 days to do this much and worried we would be out a bathroom for too much longer. We dumped every plumming clearer we could find after doing all that for a week we finally dug up the yard and cut the line and pulled it out but it's come back recently. We have yet to find anything yet to clear it compleatly.

For small jobs it's perfect. This should always be tried first

For a light blockage this thing is just the trick. Definitely zero environmental damage and very cost effective!