I have been buying these bags for years now. Now they have changed them and you can barely separate them from each other at the perforated line, let alone get the bag open to pick up poop. So are they durable and sturdy, absolutely. They are so durable now you have to have muscles to use them. I think I stood there for 2 minutes trying to get the bag separated and open after my dogs pooped. Not buying these again. Sad that they had a good thing and decided to make it "better"...like reinventing a wheel.