ESSVE Decking screw Classic intended for the installation of fencing and decking timber, etc against wooden joists, outdoors Decking screws of stainless steel grade are always recommended for very harsh environments such as marine, pool areas.NOTE! Decking screws of stainless steel grade and pre-drilling are always recommended when installing teak-like decking timber such as Cumaru, Kirai and others as well as Siberian larch.