The Ko-ken RS4010M/10-L75 1/2" Square Drive Bit Socket Set is a comprehensive 10-piece collection designed for versatility and precision in fastening applications. This set includes hex bit sockets in sizes ranging from 4mm to 19mm, each with a length of 75mm, allowing for greater reach in tight spaces. All sockets are securely mounted on a 300mm rail for convenient organization and accessibility. Crafted for durability and reliable performance, this bit socket set is an essential addition to any professional toolkit, ensuring efficient and effective operation in a variety of tasks.