Aden + Anais Swaddle Blankets

I noticed earlier that a spammer had bumped this but the spam post got removed. However, I was dying to ask about these! Do these fasten with Velcro or do you have to somehow get them to stay with just wrapping? I can never get a swaddle to stay closed unless it has velcro but it looks like (if things go ahead) we may have a late spring baby in a warm state.