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In this paper we apply a well-established eddy-current model to a 'WeldScan' probe, a more complicated type of probe, in order to better understand its characteristics. After validating the model to new experimental results, the complex interaction of the fields with defects is explored. It is then shown, that under certain simplifying assumptions on defect orientation and topology that the eddy-current signals can be correlated to defect size and location. The eddy-current model is based on a volumetric integral approach using dyadic Green's functions and has been used extensively for over ten years. The 'WeldScan' probe has been in the field for over sixteen years and has two 'tangent coils' which can be driven separately, or in tandem in absolute or differential modes. Due to the coils being 'on edge', the coupling of the probe with the work-piece is poorer than traditional coils; however, the coils orientations allow for better probe access and form characteristics. Another advantageous characteristic of this probe is the large, uniform field that is generated at 45 deg at the intersection of the coils. The uniform nature of this field allows for much easier correlation of probe signal to defect size and location. The incident field generated by the probe was modeled and used to drive the model. Experimental results were then used to validate the model with manufactured defects in aluminum. The model was then used to show that the probe's signals can be correlated to defect size and location, with some simple assumptions on defect orientation and overall shape.