Voltage-controlled voltage source
Ideal VCVS (SPICE E): V(out+ − out−) = 10 × V(control+ − control−). Infinite input impedance, zero output impedance, no limit on voltage or current. An element for circuit theory, not a part you can buy.

Try it on the benchThe lab drops it on an empty bench and opens its datasheet card.
Pins
- control + (senses voltage)
- control −
- out +
- out −