For all you rigging and lifting pros out there, these BNYZWOT pulley blocks are serious workhorses! Made from heavy-duty 304 stainless steel, these things won't rust on you even in wet conditions or saltwater environments. The M50 size with 50mm wheel diameter and 13.5mm groove width handles ropes smoothly without damaging them. What's really smart is the 360-degree swivel design that prevents your ropes from twisting and knotting - such a time-saver when you're setting up complex rigging systems. Each pulley can handle up to 400kg load capacity, so you can trust them with heavy lifting jobs. The surface has this nice shock light finish that resists scratches and wear, and the construction is just solid - you can feel the quality when you handle them. The fixed top makes rope handling so much easier, and the smooth roller lets the rope traverse effortlessly. Perfect for construction, sailing, stage rigging, or any situation where you need reliable lifting equipment. You get three in the pack, which is great for setting up multiple pulley systems or having spares on hand. At 1104g each, they've got some heft to them but aren't too heavy to carry around. These are professional-grade pulleys that deliver exactly what you need for tough jobs!