From Reptile Systems, these are designed to provide the very best quality in UVB lighting through a compact bulb, far exceeding the quality of spiral compact UV bulbs, due to their unique shape. These are standard E27 screw fitting, and therefore compatible with most reptile fittings, and ideal for using in canopy tops, to provide UVB alongside other standard lighting.
A choice of 6% or 12% bulb is available, with both having a high 30% UVA output - meaning you have a normal looking bright light, not a blue tint leftover like some cheaper bulbs. As these are UVB, they should not be used on a thermostat, as this will inhibit the UV output, but at just 23w, they provide very little in heat, so should not have a big temperature effect on most enclosures. In small nano systems they can be used as the heat source as well.
The 6% UVB is ideal for rainforest species, such as Crested Geckos, Day Geckos, Chameleons, and many ground lizards, like skinks. They are also good for crepuscular species like Leopard Geckos who require mid level UV in bursts, whilst they are out for a few hours in the day.
The 12% bulb have a higher UVB output, and is more for desert species, or those that bask for prolonged periods, such as Bearded Dragons, Uromastyx and many Tortoise species. This is designed to mimic all-day sunlight.