I really like these. They are made of very thin plastic that is better for the environment, and the do a good job by creating individual greenhouses for seeds. Although they are made very thin, they do not collapse or fall over when filled with soil. It was a little difficult to get the domes apart, but they bend easily and they don’t break. The domes don’t snap onto the planting cup but rest on it, which is fine with me because it’s easy to remove if I want to check on the moisture or growth ofSee full review