How's this for a neat twist on the traditional tape measure? This unique tape takes accurate measurements externally and internally. It features a blade with scales on both sides. The upper scale starts at zero and functions normally for external measurements. The scale on the reverse side has had the length of the case deducted for spot-on internal measuring. This is a huge advantage when measuring in a gap such as a window reveal or alcove. Use the scale on the reverse for a direct reading. No more having to calculate by subtracting the length of the case or worse still bending the tape into the corner and guessing the correct measurement. Heavy-duty soft grip case, lock button and triple rivet double sided end hook, 25mm wide blade. Metric and Imperial graduations.