This adjustable screw-jack for scaffold is made of sturdy galvanized stainless steel and will surely come in very handy on any work site. Its' rust-resistant properties ensure this product's increased durability, so you're sure that you're getting more than money's worth. Because it can be adjusted over an 18-in range, this robust screw-jack is sure to provide a solid foundation for scaffolding frames. It's especially recommended for scaffolding along external walls. Screw jacks also meets all OSHA, CSA and ANSI requirements.