Gtechniq G4 Nanotech Glass Polish

No. Despite the name 'Glass Polish,' the G4 contains no abrasive — the SDS §3 lists only acid chemistry and a surfactant. The product works by chemically dissolving mineral deposits, water spots, and surface contamination at pH 2.5. Mechanical glass defects like wiper arc scratches require a cerium oxide-based abrasive compound to physically grind down the glass surface around the scratch. The G4 cannot do that. For actual wiper arc scratches, look at a dedicated cerium oxide glass polishing compound.

Water spots, mineral deposits, hard water buildup, and surface contamination — the problems that acid chemistry can dissolve. The product works at pH 2.5, which is aggressive enough to break down calcium and magnesium deposits from tap water and sprinkler overspray. Amazon reviewers across 397 reviews at 4.1 stars report clear, streak-free glass after use. If your windshield has accumulated film, haze from water mineral buildup, or chemical contamination, this is a strong performer.

Yes. The Rag Company's Amazon product video demonstrates G4 application technique and confirms compatibility with machine application. The milky liquid consistency works with a glass-specific foam or felt pad on a DA polisher. Use a small working amount — this is a 3.4 fl oz bottle and concentrates quickly on a pad.

The US GHS SDS (Version 1.0, issued 2020-07-01) classifies the G4 as WARNING with H319 (causes serious eye irritation — Cat 2A only). No H318 serious eye damage, no H317 skin sensitization, no H335 respiratory irritation, no DANGER signal word, and no Prop 65 warning. The product is a water-based, non-flammable formula with a flash point listed as 'not applicable.' SDS emergency contact: +44 (0)1933 445 260 (Gtechniq UK) / Gtechniq North America, Cumming GA.

Gtechniq does not address coating compatibility explicitly on the Amazon listing, and the SDS does not speak to this. Acid chemistry at pH 2.5 has the potential to degrade hydrophobic glass coatings or rain-repellent treatments — this is a standard caution for acid-based glass products. If your windshield has a Rain-X or similar hydrophobic treatment applied, test on a small section first or use a dedicated pH-neutral glass cleaner instead.