This is a 20w CDM-TC Ceramic Metal Halide Lamp with a G8.5 base. This lamp comes in colour 830 warm white (3000k) The lamps are also known as CMH-TC and HCI-TC. The CDM-TC are compact, single-ended discharge lamps with high efficiency. These CDM-TC lamps maintain stable colour over their lifetime and emit a crisp, sparkling, white light. CDM-TC lamps are frequently used in shops, shop windows, public buildings, and offices. But can also be used outdoors within floodlighting and pedestrian areas. This CDM-TC lamp boasts a 15000 average life and a lumen output of 1600 lumens. Boxed in 12s.