EYE Hortilux’s Daylight Blue Metal Halide 400W is a single‑ended HID grow bulb designed for vegetative growth. The 57816 (MT400D/HOR/HTL‑BLUE) model operates on an ANSI M59/E ballast and outputs a daylight‑like 6500 K spectrum with a high 90 CRI. Rated initial output is 29,000 lumens, and average life is 12,000 hours. The lamp uses a T17 clear envelope with a mogul (E39) base and is specified for horizontal operation within ±15 degrees. Physical dimensions are about 9.84 inches long by 2.17 inches in diameter (approximately 25.0 × 5.5 cm). These parameters make it a common choice for veg rooms and research environments where blue‑rich light is preferred; actual light footprint will depend on the chosen reflector and mounting height.
