Uniseals are rubber-like and are great to use when a bulkhead will not work, especially when trying to attach a pipe to the curve side of a bucket, drum, brute trashcan, large reservoir, or even another pipe. Just use a properly sizes hole saw to create the hold, and then insert the uniseal with the pipe following behind it. In some cases a little liquid dish soap may be used to help installing the PVC into the uniseal.