Wickes Decking Stair Stringer 3 Tread - Light Green 238 x 860mm ..21 Oct 2017 . High-quality stair stringers to allow you to quickly make steps to different levels of your deck. Pressure treated for longer life. Produced from quality Baltic pine. Robust as made from thick timber. The steps (Deck Boards) in this photo are not included. Length: 860 mm; Thickness: 58 mm; Width: 238 mm.