KOTOBUKIYA. Introducing a new unique item using wheels as a concept for the popular Heavy Weapon Unit series: Heavy Weapon Unit26 Wheel Grinder. There is a special feature to this unit due to the structure of the inner gear inside the large wheel part where if the wheel is turned in one direction, an inner blade will pop out. If two sets are used, it can be attached to other products such as Frame Arms and Hexa Gear as WheelLeg Units. This item may not fit on all plastic models due to its design.