The problem: Normal halogen spotlight transformers *can* usually be used with MR16 LED bulbs but there is an issue. Since the transformer expects at least one or more 30+ Watt bulbs to be connected to it, the voltage output when just a few 1+ Watt LED spotlights are connected can exceed the transformer's 12 Volt rating. LED spotlights are sensitive to voltage, and these "spikes" above 12 volts can permanently damage the bulbs. It is possible to still operate a standard transformer by keeping at least one standard 30+ Watt halogen bulb in the circuit, but this is very inefficient and defeats the object of using low powered LED lighting! The solution: The Androv constant voltage LED driver (transformer) shown here outputs exactly 12.0 Volts current. It has been designed for usage with our Androv MR16 bulbs. Using parallel connections, if one bulb dies, the remaining bulbs will stay on. The driver can be used to power up to 8 of our MR16 bulbs. If powering more than 8 units you just need more transformers. The driver has loop-in, loop-out primary wiring terminals so there is no need for a junction box, and it offers short circuit protection, thermal protection (to prevent overheating), surge protection and double load protection. Model: Androv ED17A-12V Input Voltage: 220V-240V @50/60Hz Output: Constant 12 Volts D.C. Rated Current: 1.4 Amps Short Protection: Yes Open Protection: Yes Double Load Protection: Yes Warranty: 2 Years CE Approved