I have had good success with these using 2x per 48" rack in multiple tiers. Easy to adjust height but the transformer gets quite warm. No problems after one season of use when on 14 hours per day, 7 days a week.
LED Grow Light for Indoor Plants,YGROW Upgraded 75W Growing Lamp Light Bulbs with Exclusive Full Spectrum for Greenhouse Vegetables Plants from Seeding to Harvest.
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