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Time of Flight Diffraction (TOFD) relies on a beam with relatively high divergence to provide suitable volume coverage. Refracting wedges provide a means of directing the beam towards the inspected volume. Most wedges are made of common polymers with acoustic velocities between about 2400m/s and 2800m/s which are 40-47% the average compression velocity in steel. This provides useful positive refraction in steels with relatively small probe centre spacing (PCS). However, when testing lower velocity materials and where access from the weld centreline is limited, it can be useful to have wedges that have lower velocities. Some applications can use water encased in a reservoir, but preventing the water from leaking and avoiding air bubbles can be problematic. A viable alternative is to fabricate the wedge from a low attenuation low velocity polymer. Examples of the quality of signals obtained using low velocity polymer are given in this paper