3 products?
Old C1. I must add though, the product itself changed the whole way I looked at detailing but they no longer make the product, nano sealants are still with us.
Megs Endurance Tyre Gel. No car ever looks clean without tyre gel. So much fact. I've used it for years and it never fails to work on finishing a car off.
There are so many different things. The rotary polisher, the DA. Spray sealants. 2/Z5, QDs, IronX...
So many but i'm going to go with clay mostly because I think the decontamination stage is so important to a good finish. Claying allows the following stages to get a glass like finish imo. Big game changer in detailing inso as far as comparing to others.