Martin Cox is a British manufacturer of brushes, applicators and chemical-resistant spray hardware, and the range here covers the practical consumables of a wash bay: chemical-resistant trigger heads and 600ml bottle and trigger combinations, a microfibre large alloy wheel brush, and graded steel wire wool in 16-pad packs. The trigger heads in particular are the parts that fail first on a dilution bottle, and replacing the trigger is cheaper than replacing the bottle.

Because a standard trigger head degrades quickly on detailing chemistry. Acidic wheel cleaners, alkaline APCs and solvent-based tar removers attack the seals and spring in an ordinary spray head, and the result is a trigger that stiffens, sprays unevenly and eventually weeps chemical down the bottle. A chemical-resistant head lasts far longer and keeps a consistent spray pattern, which matters when you are trying to apply a measured amount of product.

Its main legitimate use is cleaning glass, particularly clearing stubborn deposits and old wiper or repellent residue from a windscreen with the finest grade, and cleaning stainless exhaust tips. It should never go near paint, trim or plastic. Choose the grade deliberately, work with plenty of lubrication, and test an inconspicuous area first. If you are unsure whether a surface is glass or plastic, do not use wire wool on it.

For the faces and spokes of a clean-ish wheel, yes: microfibre is softer against a painted or diamond-cut finish and holds shampoo well, which is what you want on a wheel you maintain regularly. Bristle brushes have more mechanical bite for neglected wheels, tyre walls and arches. Most people use both, with microfibre on the visible faces and a stiffer brush for tyres. Keep wheel brushes strictly separate from anything used on paint.