.....[snip]....
One thing which I will point out is that each LED (generally) needs its own
current limiting resistor. Don't try to parallel LEDs with only one current
limiting resistor.
.....[snip]....

But, if you have a few extra volts, they CAN be placed in series.
Aren't the super-bright traffic-light LEDs usually 5-6 in series?

--Myron, W0PBV.
--
Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge
PhD EE (retired). "Barbershop" tenor. CDL(PTX). W0PBV. (785) 539-4448
NRA Life Member and Certified Instructor (Home Firearm Safety, Rifle, Pistol)