Bolt U bolt made of high quality 316 stainless steel, wear-resisting, anti-corrosion, anti-rust Boat bow eye excellent for marine and other outdoor applications Marine stern bow eye electronic polished, max safe load is 1600 lbs Stainless steel u bolts suitable for automotive, plumbing and other home and industrial applications Boat stern bow eye tie down U bolt with two plates and two nuts -1pack JY-MARINE Boat stern bow eye tie down U bolt designed for fastening products to pipe, wood, etc Suitable for automotive, plumbing and other home and industrial applications Plate and nuts included Excellent for marine and other outdoor applications. the threads are M6, not 1/4. Arm centers are 35mm apart. Unthreaded portion between plate position and thread is 20mm, so the substrate needs to be at least that thick. Installed height/width is 43mm. All parts are good quality 316 stainless steel and well made.