The Milwaukee SHOCKWAVE Impact Duty? Socket Extensions provide you with better access in hard to reach places and offers extreme impact durability in high torque applications. Milwaukee's laser-etched size markings allow for fast identification of drive size and length. The dual-hole design and ring groove allow you to easily attach and remove the extensions. All MILWAUKEE? SHOCKWAVE? Impact Duty? Socket Extensions are backed by Milwaukee's Lifetime Guarantee and meet ASME industry standards.