I made a sauna out of these bulbs. They submit heat which many claims are beneficial in addition to the infrared light benefits.
From the manufacturer: The RubyLux NIR-A Near Infrared Bulb is a human-grade, premium incandescent near infrared light therapy bulb designed for near infrared heat lamp therapy. The RubyLux emits renewing, healing infrared light in the red and near infrared wavelengths associated with pain relief, increased circulation, faster recovery times, collagen production, rejuvenation and renewal and peaks at 850nm. At 4 inches’ distance, it emits 1,431 mW/cm2.
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