Super High Pressure Sodium Double Ended lamp for Plant Growth. High red and blue spectral ratios for good photosynthesis efficiency. Great lumen output for high PAR values. Robust plants through high blue light output. High red light ratio for healthy plant growth. Economic (long average life, high lumen output, low energy consumption). Tubular low profile design for compact fixtures. The jacket of this double ended lamp is made from quartz glass. Do not handle with bare hands.