GPS Digital Speedometer for Car KM, USB Connect Plug and Play for Car Truck Motor SUV All Vehicles, Automatic Brightness Adjustment,Large Font Display

Dashboards keep getting busier while the speed reading keeps getting smaller. This unit sits on the dash, runs from a USB socket, and shows road speed in large digits worked out from satellite positioning rather than from anything wired into the vehicle.

A GPS reading is not your speedometer

The two numbers are arrived at differently. A vehicle speedometer is driven from the driveline and is influenced by tyre diameter and wear; a satellite unit calculates speed from change in position over time. They will usually sit close together, and they will not always agree. Your vehicle's own instrument remains the legal reference for the speed you are travelling at, and this display does not stand in for it. No accuracy figure is published for the unit, so none is quoted here.

Plug it in, and that is the installation

Power comes from a USB port. The supplier lists cars, motorcycles and trucks, which in practice means any vehicle with a 5 V USB source available. There is nothing spliced into the loom, no sensor to position and no calibration step. A light sensor raises and drops screen brightness on its own, so the digits stay readable in full sun without glaring back at you after dark.

Specifications

• Speed source: satellite positioning
• Units: km/h, per the title
• Power: USB
• Display: large-font digits with automatic brightness adjustment
• Stated accuracy: none published
• Dimensions, weight, cable length and operating voltage: not given

Before you mount it

• The vehicle's own speedometer remains the legal reference. Confirm the requirements that apply to your vehicle and your state regarding devices mounted in the driver's field of view before fitting it for road use.
• Position it where it does not obstruct your view of the road, and not in front of an airbag.
• The supplier notes that all satellite positioning equipment drops out briefly in tunnels, in underground car parks, and in rain or fog. Open sky gives the steadiest reading.

A large, readable second opinion on your speed — not a replacement for the instrument in front of you.