A simple clock made from three gauges - or just one. Accurately displays mission elapsed time in seconds, minutes, and hours, starting from the time the level is loaded.

There are actually four clocks. Three are fully customizable, made from a combination of three separate gauges. The colors, sizes, and styles of each hand can be adjusted individually. These clocks are available in three standard sizes: one at 70%, one at 100%, and one at 150% scale. However, they can be fairly easily resized to fit in whatever you need it to fit into (though do note that the individual gauge parts are not all the same size, and adjust their scales accordingly).

The fourth clock (the one with the red screws) is a special one-part clock (suggested by asteroidbook345). This clock combines all three hands into a single gauge part, and is therefore even easier to drag-and-drop into your own aircraft. However, the disadvantage of the one-piece clock is that the hands must all be the same color and approximate size, though the indicator styles can still be changed individually. This clock can easily be resized to any diameter you want in seconds.

Instructions

Grab by the base of the gauge and drag the clock to your subassemblies. Nudge it into place manually with the Connected Parts option toggled (to ensure you move all three parts of the clock together). You may need to manually make connections, as connecting one gauge to another gauge seems to prevent that gauge from automatically connecting to other parts.

All three clocks have zero weight and drag.

No permission needed to use, though I'd appreciate if you give credit.

If you want a more "modern" version with a digital display included, check out Gauge Clock 2.