Question for those with flat black or satin hoods
No it doesn't stain it it may leave a small film that is easily removed with modern paint protectants. my car came with the factory flat black hood so I've been dealing with it for 30 years or so before my new paint job I just would armorall the hood and it always came out looking Sharp defect free. But now after my new paint job I just use turtle Wax exterior detailer
