Challange Limitations with the Crux 600 Head. The Crux 600's new Droprail technology gives this head a minimized sidewall design that drives the ball to the sweet spot for maximum control and hold permitting a wider range of motion. The new Speed Scoop protects the top strings and improves ground ball pick up minimizing drag. The 10 degree head creates a perfectly balanced stick allowing for quicker releases on passing and shots. The Crux 600's Launch II Pocket has strategically targeted flex points at the sweet spot which maximize hold making this one of the most advanced heads on the market with superior control and feel!