LED R20 light bulbs have a face diameter of 2.5 inches and are designed to replace incandescent R20 bulbs in 4 inch recessed cans and in other R20 applications. The LED bulbs save up to 85% on energy costs compared to incandescent and offer a long 15,000 to 25,000 hour rated life. The LED bulbs in this category also include options for neutral white (3000K), cool white (4000K) and very cool white (5000K) illumination. Dimming is a standard feature. If you need assistance, call 800-784-1998 to speak to a lighting specialist.