Tekton 4 mm Bit Sets are ideal for small electronics. The variety of small bits allows you to repair mobile devices, laptops, video game consoles, controllers, wristwatches, and a wide range of other small electronics. The bits are made with tight tolerances for a secure fit in small screws, reducing slip and wear—crucial for high-value, sensitive electronics. The tip size and Tekton “T” are clearly stamped onto every bit. The bits are made from hardened 8660 steel (HRC 55–58) and finished with a zinc phosphate conversion coating that provides lasting corrosion resistance without altering dimensions or flaking, unlike chrome finishes. The flexible rail securely grips the bits so they can't fall out, while also making it easy to remove any bit one-handed. The rail can also stand upright on a flat surface, making the markings easier to see. High-contrast size markings are printed on the top of the rail.