4 Pin Compact Fluorescent
T5, 5/8 inches (16mm)
36-watt, twin-tube, 4-Pin, Long Compact Fluorescent UVA-1
Twin-tube long compact fluorescent bulbs have very high power density and provide much greater irradiance than single-tube T12 bulb types. Also known as Philips PL-L36W/10. May or may not be Philips brand.