Ballast is completely enclosed in arm, but is readily accessible. All components in single carton. Refractor available in open bottom acrylic, or polycarbonate. Open-rated sockets used on MH units; use open-rated MH lamps 6’ of supply wire and hardware included. Mounts to flat wall and poles a mininum of 3.5” diameter. Suitable for -30°C MH / -40°C HPS. Complies with ANSI: C136.2, C136.10. Constant-wattage autotransformer.