Colour-change iron removers have become very popular due to their effective action and spectacular reaction when they come into contact with near-invisible iron contaminants. Whilst they will never be a complete substitute for claying, they can decrease your clay's workload and work brilliantly on wheels as a wheel cleaner. The Ferrous Dueller recipe uses a "lower" odour active ingredient to keep the unpleasant smell of these products to an absolute minimum, and blends this with surfactants to boost cleaning power (really useful on wheels). It also has a little more "cling" than some other iron removers, to increase dwell time - yet it remains easily sprayable.
H302 - Harmful if swallowed.
H317 - May cause an allergic skin reaction.
H318 - Causes serious eye damage.