3 Series 3010-E, glow-in-the-dark/ultra reflective letter-E, these highly visible markers are ideal for clearly identifying electrical utility equipment such as electrical boxes, pedestals, transformers and utility poles. The numbers and letters are also optimal for facility identification and general purpose marking such as aisles, equipment, shelving and bins. Legend is "E", size is 3-1/2" Height, 2-1/2" Width, character height is 3", color is black, glow-in-the-dark border/silver, material is high intensity prismatic reflective sheeting and photoluminescent material with a pressure sensitive adhesive. Illumination characteristics are illumination - 21.6 lux (2 foot-candles) for 2 hours with a 4100K cool white fluorescent lamp. Luminance (after illumination) is 10 minutes