Hydrofarm Philips Master 3100K GreenPower Elite Agro CMH Lamp, 315 Watt, T-12

Superior color quality. Crisp White light. 4200K Color temperature, high 92CRI, 34, 300 initial lumens (109Lm/W). high 90% Lm maintenance at 8, 000 hr./High 85% ppb maintenance at 20, 000 hr. Unique open rated lamp construction reduces radiant heat from the arc tube & is suitable for open fixture use.important:until the lamp has achieved a least 10 hours of operation, The lamp should never be turned off sooner than 2 Min, including during the installation test. In case that this has happened, you will have to wait 1 hour before switching on again. Failure to comply with this requirement may lead to ignition problems.