Concrete door stoppers are the best ones because they are heavy enough to keep the doors in place, so no more door slamming. To make ones yourself take 1 meter of rope or very thick twine, galvanized coupler x 2, tape, a milk or juice box and one round plastic container, concrete mix of your own choice. Cut the rope into two similar pieces using a sharp knife. Then wrap the ends with a tape to prevent them from splitting. When that’s done, place them together in a coupler until they sit tight. To prepare concrete mix simply follow the users manual from the packaging and stir it well together, then quickly put the mixture into the molds. Finish the project looking here.