The MILWAUKEE® SHOCKWAVE™ 3" Impact Magnetic Drive Guide is engineered for extreme durability. The magnetic drive guide features optimized Shockzones that absorb peak torque and prevent them from breaking. Each Custom Alloy76 Steel drive guide has a stainless steel sleeve that slides over the fastener for improved stability. The drive guide barrels have laser-etched depth gauges for increased fastener control. The Milwaukee magnetic drive guide holds fasteners to the guide with a C-ring to retain the insert bit for maximum efficiency.