DIYers and workshop folks, this Hirate caster wheel set is exactly what you need to make anything mobile! You get four casters total - two with locking brakes and two without, plus the necessary 1/2-13 threaded nylon lock nuts for installation. The imperial stem size is 1/2-13 with a stud diameter of 1/2 inch and length of 0.79 inches (20mm) - important note though, these won't fit metric M12 sockets, so double-check your equipment before buying. The locking casters are super handy - they brake the rotation of the wheel while still allowing the stem to swivel for direction changes. Made from high-tech elastic polyurethane, these wheels roll quietly and smoothly without getting stuck on crumbs, hair, or damaging your floors. The industrial-grade construction means they can handle serious weight and regular use without failing. They're perfect for transforming flight cases, instrument cases, display equipment, dollies, tool boxes, light machinery, furniture, or any project where you need mobility. Installation is straightforward if you're familiar with basic tools - just screw them into the threaded sockets. Hirate backs each caster with a lifetime replacement warranty, which shows they stand behind their product quality. Whether you're building custom furniture, upgrading workshop equipment, or just want to make heavy items easier to move around, having quality casters makes everything so much more convenient. The value is excellent for what you get - four heavy-duty casters with half of them having locking functionality. If you do any kind of DIY projects where mobility would be helpful, this caster set is absolutely worth having in your workshop supplies.