I ordered this very expensive motorised rooflight but when my builders fitted it, whwn opening and closing it was jerky in the extreme, stopping and starting. We complained to EOs, they took a very long time to come and look at it, and then saud they couldnt fix the problem. Another long delay until another person visited who was extremely helpful and had what they thought was a fix to make opening abd closing it much smoother. It is a little smoother but still jerks and makes odd sounds as it opens and closes. So not what you would expect from a rooflight that cost £1500. I regret buying it