SOMFY Power Supply 14" 5-Din Rail (MPN #9011975)

To get started, first choose the window covering you are interested in. When measuring to fit blinds or shades to your windows, it is important to remember a few key things. Decide if you want an inside mount or an outside mount before you begin the measuring process. A steel measuring tape is much more accurate than cloth measuring tape. Always measure to the nearest 1/8 inch. Don't round to a half or whole inch. Be careful about transposing measurements. Be sure to always have width and height clearly marked. And remember: always put your width measurement first, and height last (W x H). Then read our Measuring Guide.