This Philips HF-R 218 PL-T/C dimmable ballast runs a 2 x 18w compact fluorescent lamp. This ballast's lamp power can be regulated from 1% to 100%, automatic stop start, automatic restart after lamp replacement, up to 75% reduction in energy consumption and quick programme flicker free start.The Philips HD-f ballasts are commonly used in offices. These units are for use with installations with emergency back up.