This is the Gear Set for use on the Revell Proto Max RTF Helicopter.      
                                                                               
FEATURES: Nylon construction                                                   
          White in color                                                       
                                                                               
INCLUDES: One Nylon Gear                                                       
                                                                               
REQUIRES: Installation on the helicopter                                       
                                                                               
SPECS:    Outer Diameter: 25.5mm (1")                                          
          Inner Diameter: 3mm (0.12")