These are Aluminum Hex Wheel Hubs for the T-Maxx and E-Maxx Truck Kits.    
                                                                               
FEATURES: Blue anodized.                                                       
          Machined 6061 T-6 aluminum construction.                             
          Packaged in foam, on a bubble sealed header card.                    
                                                                               
INCLUDES: Four Hex Wheel Hubs                                                  
          Four 2.5 x 10mm Axle Pins                                            
                                                                               
REQUIRES: Assembly onto the truck.                                             
                                                                               
SPECS:    Width:         13.0mm                                                
          Inner Diameter: 6.3mm