High performance, low total cost of ownership Flexible lighting solution - available in various bases and wattages.;Long Life when compared to switch start metal halide (for 175W and 250W versions). Philips Pulse Start Metal Halide Lamps offer an optimized metal halide system for greater efficiency and lumen maintenance. Up to 25% increase in maintained light output over standard metal halide.;Increased efficacy (up to 120 lpw) equals low total cost of ownership.;Up to 50% faster warm-up and restrike time.;Up to 50% increase in life when compared to switch start metal halide (for 175W and 250W versions).;ED-37 base available in 350 and 400 watts base up and horizontal operations as well as COATED / BT-37 available in 750 and 1000 watt base up operation and 750 watt horizontal operation / ED-28 available in 175, 200, 250, 320, and 400 watts base up or horizontal operations. 175 and 320 watts of the ED-28 base are also available in COATED. Ideal for industrial and retail high/low bays and parking lots.