This Velux Deck Mount Skylight Flashing Kit is designed for deck-mounted skylight installations and fits a rough opening of approximately 21" W x 45.75" L. The kit is in like-new condition; however, the adhesive underlayment is not included and will need to be sourced separately. All other flashing hardware components are included. Velux flashing kits are engineered for durability and weather resistance, making them a reliable choice for any roofing project.