This is the Hitec Karbonite Gear Set for the HS-635HB and HS-6635HB servos

FEATURES: Karbonite construction

INCLUDES: Four gears

REQUIRES: Disassembling HS-635HB or HS-6635HB servo  

BOX DIMENSIONS: 2.25" W. X .75" H. X 3.00" L. BOX WEIGHT: .01 LBS.