Match the screen size and model — most are between 5 and 7 inches — and fit film rather than glass. The damage here comes from being stored loose with keys and coins, not from drops, and film handles that for a couple of pounds.
Why sat navs scratch
- Glove box storage. The device shares a space with keys, coins, pens and ice scrapers.
- Mount removal. Pulling a unit off a suction mount usually means gripping the screen.
- Windscreen heat and sun. Long exposure makes coatings and adhesives age faster than in a pocket.
- Glare. Mounted low on a windscreen, these screens reflect the sky and the bonnet.
Matching the size
| Device | Typical screen | Protector |
|---|---|---|
| Compact sat navs | 5-inch | Film; cheap and plentiful |
| Mainstream sat navs | 6 to 7-inch | Film, matte if glare bothers you |
| Truck and caravan units | 7-inch and up | Film; check bezel depth |
| Dash cams | 2 to 3-inch | Rarely worth it; the lens matters more |
Sat nav model ranges repeat names across years, exactly like less common tablets. Match the full model name and the screen diagonal; a 6-inch sheet on a 7-inch unit leaves a strip of bare glass that then collects the scratches.
Film, not glass
These screens are flat, small and never dropped from height. Film is thinner, costs little, doesn't change touch feel much and can be replaced every couple of years as it wears. Glass is heavier than the problem requires and more likely to lift in heat.
Dash cams
Dash cam screens are tiny and mostly used for setup. Protecting one rarely pays off, and anything that covers the lens is a bad idea: an extra surface in front of the lens causes reflections at night, exactly as it does with phone camera lens protectors.
Questions people ask
Do sat navs need screen protectors?
They scratch more than you'd expect, mostly from glove-box storage and handling at the mount. Cheap film prevents most of it.
Should I put a protector on a dash cam?
Rarely worth it on the small screen, and never over the lens, where an extra surface causes night-time reflections.