Grade 70 chains, often made from high-strength steel, are primarily used for towing and securing loads, making them ideal for heavy-duty applications like truck towing and trailer securing. Grade 43 chains are commonly found in rigging applications, offering reliable performance for lifting and hoisting tasks. Grade 30 chains, while not as robust as Grade 70 and Grade 43, are still valuable for lighter-duty applications, providing a cost-effective solution for various tasks. Proper maintenance and regular inspections are crucial to ensure their longevity and performance in demanding environments.