These garden lights run on 12V AC, from an isolating transformer. The cable is a twin / figure 8 style, and the lights have spiked connectors which clamp over the insulation and pierce through it to make the electrical connection.
Originally fitted with 7W incandescent lamps.
The original lampholder and wiring had corroded, and rather than obtain replacement lampholders, some G4 LED discs were fitted instead. These have pins, but the pins can easily be removed so that the wires can be soldered directly.
The LEDs are 1.6 watts, less than a quarter of the power of the original filament lamps, yet are actually brighter than the original.