G5 t5 fluorescent bulb master tl5 heho secura with shatter protection philipsthe fluorescent bulb with 16 mm diameter and shatter protectionadvantages higher degree of effect than 26 mm fluorescent bulbs through optimisation of the light current at 35c allows for further system miniaturisation and maximum freedom in lamp design nearly constant light current throughout the lifespan good colour reproduction level 1b ra80 fep teflon coating particularly heat resistant up to 200c