Eye Hortilux 901680 PowerVEG Multi-Color Pack, 4' Provides nanometer specific spectrums to further enhance the powered full spectrum + (fs+uv) grow lamp during the vegetative and flowering growth cycles Combining the fs+uv with the colors allows for structurally sound plants ready for transition to hid where bigger and better yields and more overall production will be seen Comes in four colors: 420, 460, 633 and 660