From a technical point of view, there are currently three main modes of high-definition video technology: 1. 720P: 1280 × 720 (non-interlaced, field frequency is 24, 30 or 60) is D4 standard digital TV display mode, 60hz frequency, 750 vertical scanning lines, 720 visible vertical scanning lines, 16: 9, remember 720p or 750p. 2. 1080i: 1920 × 1080 (interlaced, field frequency 60) is the D3 standard digital TV display mode, 60hz frequency, 1125 vertical scanning lines, 1080 visible vertical scanning lines, 16: 9, which is recorded as 1080i or 1125i. 3.1080P: 1920 × 1080 (non-interlaced, field frequency is 24 or 30) is the D5 standard digital TV display mode. Naips LED Emergency Down Light is specially designed for ceiling recessed emergency lighting. Automatically light at once when buildings main power outage. NON-MAINTAINED type and it can customized the emergency time for different wattage. We can also add the LED emergency driver kits to match different kinds of your LED downlights. Led Downlight With Emergency Backup,Downlight With Emergency Backup,Emergency Light Downlight,Led Emergency Downlight Foshan Nai An Lighting Electric Co.,ltd , https://www.articalight.com