Carefree IE0407C00 SL Premium Indigo Blue 4.0' Long RV Camper Complete Window Awning with White Arms (Indigo with White Wrap and Red Tenera Thread) Made with Carefree's PREMIUM 15 oz.; vinyl, double hemmed and double stitched with virtually indestructible Red Gore TENARA thread to help ensure fabrics will last; PREMIUM fabric is embedded antimicrobial protection for added durability; Simple manual operation; Fabric is attached using a standard awning rail (included); Each arm is attached at the bottom with three screws through the bottom support and pivot bracket; Standard Extension of 19"; Standard Arms-Fits window up to 36" Tall; Arms are 18" Tall Measurement of window awning roller is center of arm to center of arm; To calculate the awning length you need measure the window length (outside of frame to outside of frame) then add 6" and round up to the nearest window awning size available; Bottom Bracket on the awning arm measures 2" wide x 1" tall; Fabric will measure 6" less than the awning size stated