The Stanley Proto J5210H socket is built for dependable fastening performance in automotive, industrial, and mechanical applications. Featuring a 5/16" SAE size with a 3/8" drive, this professional-grade 6-point socket provides secure fastener engagement while helping reduce fastener rounding during use. Constructed from durable alloy steel with a polished chrome finish, it offers long-lasting durability, corrosion resistance, and easy cleanup. Ideal for professional technicians, mechanics, and everyday repair tasks.