Agrobrite T5 4' Replacement Lamps, 6400K, 54W, case of 20In the pack, you get at least 20 T5 replacement bulbs which offer HO output at an affordable price. With the replacement bulbs, you can achieve healthier yields indoors as the former gives out 6400K color temperature, which is equivalent to the natural daylight temperature. The grow light is durable and promises a long lifespan of 20,000 hours, so no untimely expenditures. The replacement bulbs are compatible with the T5 fixtures by Agrobrite. The 54W