Feature: Made of exceptionally heavy duty zinc-plated solid steel, anti-rust ability, durable and long life. Can be easily fastened with just two bolts and basic hardware on metal surface or wood floor. Comes with 8pcs M4 screws for installation. Specification: Single Weight: 294g Material: Galvanized steel Ring Size: 5.5cm x 4.1cm x 0.7cm Mounting Bracket Size: 4.1cm x 3.6cm x 0.2cm Screw Size : M4*25mm Hole Diameter: 6.5mm Package Includes: 4 Pcs heavy duty D lashing rings 4 pcs mounting brackets 8 pcs M4*25mm bolts.