The Puck Retrofit System: 1 Module, Infinite Applications. An indoor/outdoor, retrofit lamp designed for use in vertical or horizontal, opened or enclosed fixtures. Replace your metal halide or high pressure sodium bulbs and make the switch to The OEO LED PUCK. Saves 71% in energy costs - Simply bypass the ballast and change bulbs! The OEO PUCK Series is fully customizable and can be built to fit any fixture.