We are purchasing a Korniche roof lantern and Modern UPVC Windows offer an excellent single source of information to a potential customer compared to lots of other retailers. Sizes are customisable to the mm and all trim and glass combinations are available. They provide comprehensive information from the manufacturer to ensure you specify and select the correct product. Purchase process appears to be straightforward but did appear to have a technical glitch first time around which has been reported. Order placed at time of review, waiting for the sales process to complete and product delivery.