The Sealey 1/2" Drive 4mm Hexagon Socket Bit is the smallest size in this professional range, perfect for accessing compact hexagon fasteners in confined spaces. This 4mm socket is particularly useful for precision work on smaller components, electronics enclosures and delicate mechanical assemblies where larger tools simply won't fit. Constructed from forged Chrome Vanadium steel with a precision S2 steel bit, this socket delivers reliable performance despite its compact dimensions. The heat treatment process enhances the material's hardness, whilst the chrome plated finish with fully polished mirror surface provides excellent corrosion resistance and easy maintenance. The integrated knurled ring ensures you maintain a secure grip even when working with oily fingers, a crucial feature when handling smaller fasteners that require careful control. Whether you're working in automotive, electronics or general engineering applications, this 4mm socket provides the quality and reliability S