This kit enables you to drive 6 series leds from a single Arduino output pin. (note the leds will be all on or all off it does not allow you to control individual leds). When you put leds in series the voltage needed to drive the chain increases by led Vforward x the number of leds. so to drive 6 leds with a Vf of 2volts you would need >12 volts and the current limited to Iled (20mA typically). So to power this board you will need a bench supply or power adaptor capable of suplying slightly more than the Vf x 6 value so for the kit greater than 18volts DC. You can of course reduce the number of leds but each empty position will need to have a shorting link fitted across the led holes. The pcb as shown (141mm x 22mm) has the 6 leds at 18.5mm pitch and was designed for the 10mm leds as supplied in the kit, but of course you can use smaller leds if required.

What's in the kit a quality pcb single sided, silkscreened, solder masked and lead free, 6 x 10mm water clear green leds 3-3.4Vf, 1 TIP transistor NPN, 1 base resistor 1K, 1 current limiting resistor set for the green leds supplied and a 3 pin header.

Full instructions will be sent and it is easy to test this using the blink sketch. Connect the V+ pin to your bench supply positive terminal GND to the bench negative terminal and the Arduino (normally pin 13 ) to the IN pin and run blink.

If you use a pwm pin instead of pin 13 you can do an analogWrite and dim the leds.