Overview Product Description A T handle hex head wrench used to tighten or loosen the muscle chuck. 4 mm or 5/32 inch T-handle hex key Product Videos Custom Field Product Reviews Write a Review Write a Review × Musclechuck MuscleChuck T-handle hex key for woodworking quick router bit changer Rating * Select Rating 1 star (worst) 2 stars 3 stars (average) 4 stars 5 stars (best) Name Email * Review Subject * Comments *