ARRMA 3S 4S Brushed Red Aluminum Alloy Center Gearbox + 57T Metal Center Gearbox Assembly, including Pan Head Hex 2.54MM 2P and Lock Cup Head Hex 314MM 3P
Full Metal Motor Seat Center Gearbox Housing. It has a more attractive appearance, provides better heat dissipation for the motor gears, is less prone to deformation, and makes the gear motor more durable. It comes with a 57T chrome steel large gear inside.