Pack out more with your current case. The Stackable Bit Holder acts as an expansion to the 21 bit holder found in the Fix It Sticks' Medium and Large cases*. With twelve 1/4" Bit slots this holder expands your storage capacity by ten bits without upgrading to a larger case. 

*Large Case: The Works kits
  Medium Case: AR Toolkit, MPX/MCX Toolkit, & Rifle and Optics Toolkit with Individual Torque Limiters