For brightness，5W>3W>1W4. 5W（4pcs chip,4 in 1）,3W(single chip),1W(single chip). The 3w bulb can be used as 1W bulb. 20mm heat sink PCB(UP TO 1mm thickness),the leds have been sealing-in. Only for Royal Blue (445-455nm)and 660nm red light and Full Spectrum 400-840nm led bulb ,they can be used for Plant Growth Lighting.
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