This set of 4 U-bolts with plate hex nuts is made of high-quality zinc and has a 1/2 x 3.5 x 6-inch size. The brand is National Mfg/spectrum Brands Hhi and they are designed for use in home improvement projects. These bolts are perfect for building and hardware applications and are a great addition to any toolkit. The type is U bolts and they come with a plate hex nut design for easy installation and removal.