Actually the correct answer to the question is
RAT WAX
Specially Formulated for Rods & Kustoms with Flat, Matte, & Satin Paint Finishes.
WHAT IS IT?
Rat Wax™ No Shine Car Soap and Rat Wax™ No Shine Detailer are the first products of their kind. They are designed specifically for rod & kustom cars with flat, matte, and satin paint. Rat Wax™ No Shine cleans and protects in one easy step. While the product name implies that it’s a “wax”, it really isn’t! After all, you can’t “wax” these types of finishes. Rat Wax™ No Shine removes dirt, dust, water spots, grease, tar, fingerprints, grime, oil, fuel, & bird droppings from your car's unique finish. Rat Wax™ No Shine also leaves a clean natural look and an invisible layer of UV protection against the fade of the sun, rain, and other harsh elements.
WHY YOU NEED IT!
Flat, matte, and satin paints normally have a very thin and porous coating, so you need to be extremely careful in what you use on them. Most waxes, detailers, and soaps, have either a petroleum base or gloss enhancers that contain high pH levels, which will damage these types of finishes, by changing its original sheen to a shine. That’s not something you want, since it can’t be undone. BE SAFE! Only use Rat Wax™ No Shine products to wash and clean your rod or kustom.
For more info visit:
http://ratwax.net