Zipline by Leviton, integrates the ballasts and lampholders required for retrofitting linear fluorescent fixtures into a single, pre-wired unit. Suitable for most 2'-by-2' and 2'-by-4' troffers, the system comprises just two individual components, which reduces the typical installation, field repair, and replacement times required for retrofitting fixtures. Zipline comes in high, normal, and low ballast factors, and in two- and three-lamp configurations. It offers a 5-year limited warranty and has an optional snap-in reflector. leviton.com