Boston Gear's stock helical gears are manufactured in both right- and left-handed configurations with an industry standard 45° helix angle to transmit motion and power between non-intersecting shafts that are parallel or at 90° to each other. For parallel shaft operation, helical gears with opposite-hand helix angles are required. For shafts at 90°, a same-hand helix angles must be used.

For parallel shaft applications, the overlapping tooth contact of our helical gears provides smoother, quieter operation and higher horsepower capacity than spur gears of comparable size. For 90° shaft applications, the tooth-contact area of helical gears is very small, making it ideal for applications requiring only limited load carrying capacity.