Meguiar's Ultimate Black Plastic Restorer

Community reviewers on daily drivers report 2–4 weeks of darkened trim before noticeable fading. This is typical for surface-coating restorers — the mineral oil and silicone formula coats the trim surface but does not chemically bond with the plastic, so washing and rain gradually remove it. The manufacturer does not give a specific week or month claim on the current 16oz label. Re-application every 3–4 weeks keeps trim looking consistently dark.

It can, especially if it rains before the product has fully cured on the trim surface. Multiple forum reviewers have documented the product running from trim onto adjacent painted panels during rain events, and it can be difficult to remove once dried on paint. Applying carefully, avoiding over-application near painted surfaces, and allowing the treated trim to cure overnight before the car is exposed to rain reduces this risk significantly.

It is a surface coating. The SDS identifies white mineral oil and organo-modified silicone as the primary active ingredients — these coat and darken trim by filling the surface texture rather than bonding chemically with the plastic substrate. This produces good results quickly and is forgiving to apply, but the durability (2–4 weeks) is shorter than penetrating polymer or acrylic resin restorers.

The SDS classifies this product as a Skin Sensitizer Cat 1A (H317) — meaning repeated skin contact can trigger an allergic reaction in sensitive individuals. The SDS also notes a suspected reproductive toxin ingredient (H361) at low concentration. The SDS §8 specifies nitrile gloves as the skin protection measure. Outdoor or well-ventilated application is preferred; the SDS §8.2 notes respiratory protection where ventilation is inadequate, relevant to individuals sensitive to the CMIT/MIT preservative present at trace levels.

The product is marketed for plastic, vinyl, and rubber exterior trim. Community reviewers confirm it darkens rubber (door seals, window trim, EPDM moldings) effectively, with results similar to plastic — good immediate darkening that fades gradually over weeks. EPDM rubber tends to hold surface coatings slightly longer than smooth ABS plastic because the more porous surface texture retains the mineral oil film. Multiple applications at the start of the season can help build lasting coverage.