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Yup thats a rack & pinion.
Nothing to fret about, the modern ones are great if they have the teeth on an angle like that (and a matching helical pinion) - it means it will be smooth. The key aspect of the Crayford - which I think almost every manufacturer has adopted - is the use of 4 tiny precision bearings to support the draw tube rather than a sliding friction bearing.
The rack & pinion IMHO has a big advantage in its ability to hold heavy loads without slipping whereas a crayford roller drive needs some sot of adjustable drag or a locking screw if you're using a heavy eyepiece or camera.
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