gearbox and steppers

I found a Compumotor Stepper, that would fit a need that I have, but it has a
right angle gearbox on it. Will this gearbox introduce extra backlash, or is
it something special for steppers, it is driving a ball screw just the right
length for my needs.
Would the gear box be removable? Kind of hard to see as it is still in the
unit. Any suggestions comments will be greatly appreciated.
bill
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