These are both E26 bases, which can be used universally on light fixtures, saving energy and money.
8W ST19 LED light bulb is equivalent to 100 watts incandescent light bulb ,saving even more than 90% energy,with an astonishing life rating of 15000 hours
4.5W B11 LED light bulb is equivalent to 60 watts incandescent light bulb ,saving even more than 90% energy,with an astonishing life rating of 25000 hours