Lamps classified as O-type, like this one, comply with ANSI standard C78.389 for containment testing and may be used in open luminaries. See manufacturer lamp warning.
When operated on ballasts having a sustaining voltage less than 270V, lamp life may be significantly reduced.
Lamps may be operated on ANSI M132 (320W) Compliant ballasts.
ANSI M154/O:M132/O:M131, M131/O. Dual wattage 320/350W Metalarc Pulse Start high output, position oriented, reduced color shift, open fixture rated pulse start metal halide lamp, clear, base up burn within 15deg.