The Advance 71A8473-001D Core & Coil Ballast Kit is a magnetic HID ballast assembly rated for 400 watts and designed for a single high-pressure sodium lamp in industrial luminaires. It uses the S51 ballast family with ANSI code M169/S51 and accepts a 120 V input, making it a direct-replacement style kit for compatible fixtures. The kit is used to replace 400 W HID ballasts in fixtures that require a single-lamp S51 configuration. Philips Advance part 71A8473-001D appears in distributor catalogs and cross-reference guides under that exact part number.
