Screw rod specification:The pack comes with casters set of 4 low profile caster wheels , Stem Diameter 0.3"(8mm), Stem Length 0.59"(15mm) Threaded Stem Casters Swivel Casters TPR Wheels & 360 Degree Rotation: Each of the workbench caster wheels are made from superior sturdy Polyurethane materials and is well constructed. You can glide the swivel casters effortlessly on wooden floors and carpet as you are guided around corners,It's very quiet and doesn't hurt the floor Double Ball Bearings & Strong Load Capacity: These 1 inch low profile caster wheels are designed for furniture, providing smooth, silent, and sturdy rotation. Each wheel has a loading capacity of 20lbs, with a total capacity of 80lbs Multiple Applications: The furniture workbench caster wheels can be widely used for a workbench, wood box, kitchen table, cabinet, furniture, and other items commonly found in the workshop, garage, kitchen, factory, and office. It’s very convenient for you to clean the floor by moving the workbench smoothly SATISFACTION GUARANTEED: Your satisfaction is our top priority. The stem size is M8 (15mm in length)—please confirm measurements to ensure a proper fit. We are equipped with four nuts and a simple wrench for easy installation MyyYiTar Stem Threaded Mini Casters