OSB 3 T&G (Tongue and Groove) is a type of oriented strand board that has been designed with a tongue and groove profile along its edges, which allows the panels to interlock seamlessly and create a strong and stable joint. The dimensions 2440x590x18 refer to the length, width, and thickness of the OSB T&G sheet, which is commonly used in flooring and roofing applications. The tongue and groove profile allows for easy installation and ensures a tight and secure fit between adjacent panels. The thickness of 18mm provides good structural strength and stiffness, while the panel size of 2440x590mm allows for quick and efficient installation with fewer joints and seams to worry about. OSB T&G is a popular alternative to plywood and other materials for flooring and roofing, as it is cost-effective, durable, and easy to work with.