The numerical value represents the diameter of the bulb in 1/8 of an inch.
Common measurements:
Color temperatures range from warm white to cool white.
2700K - 3000K – provides an ambient, intimate, and personal mood with its warm white light that is ideal for living rooms, family rooms, and hospitality environments.
3500K - 4100K – provides a clean and efficient neutral white light that is ideal for kitchen, bath, garage or commercial applications.
5000K - 6500K - provides a vibrant and alert cool white light that is ideal for commercial, industrial, and institutional applications.