The Screw-in hooks are made of 304 Stainless Steel. These screw hooks are stronger and more durable than those made of iron with coated surface of Nickel/Zinc/Vinyl, and especially more reliable for outdoor hanging. The screw in hooks sizes are as follows: 10 pcs 40mm length hooks, 10 pcs 50mm length hooks and 10 pcs 65mm length hooks, 30 pcs in total. Among product pictures there is a data sheet, which indicates all necessary dimensions of the cup hook, including total length, thickness, internal diameter, outer diameter and thread length. This contributes to an easy picking up decision for users,and is no bother of size matching problems in their projects. 30 pcs hook screws with 3 sizes from small one to large one, this could cover most occasions when a hanging screw hook is required in a project. The eyelet screws could be used in gardens and kitchens. The thread end is to screw into wooden material, such as fences, wooden beams and cupboard board, while the hook end is to hang things like lights, ropes, chains, feeders and so on.