Columbia Throttle Box bullnose roller With the exception of the

With the exception of the flat boxes

Low Center Of Gravity No-Flip Design

while keeping it aligned in the corner

Air Flow - No air flow control — vent remains open at all times

Columbia Throttle Box bullnose roller With the exception of theThe Throttle Box is another great product of ours that offers years of great performance. All billet construction with a threaded stainless steel ball, this Corner Box looks and operates seamlessly. All our Corner Boxes now come standard with automatic capabilities, making pushing the box at least 50% easier than standard boxes. The new springs have adjustable tensions and greatly reduce the occurence of air pockets while running. The Throttle Box