Hi mate, i find this type of multi plug best for a pc fan, if you cut the adaptor of the end, shred the wires back and connect them to the pc fan, job done.
If you get the one with diff setting's for the volts, (like in the pic)it kinda works like a fan speed, so the higher you move the switch to the faster the fan goes, works a right treat to be fair
Hope this helps
Peace
DZ