Experiments suggest that using head-up displays like Google Glass to support parts picking for distribution results in fewer errors than current processes. Making Glass opaque instead of transparent further improves selection efficiency. The Web extra at http://youtu.be/yUZFaCP6rP4 is a video demonstrating that order picking assisted by head-up display (HUD) is faster, has fewer errors, requires less workload, and is preferred to order picking assisted by pick-by-light, paper pick list, and cart-mounted display (CMD). The second Web extra at http://youtu.be/RApBJ0U3XpI is a video demonstrating that order picking assisted by a Google Glass with an opaque display is three percent faster than with a transparent display (default).