UVB is critical to the health of our chameleons. Since we cannot see UVB light, the best way to ensure you have the right levels in your cage is to have a UVB meter. The Solarmeter 6.5 is the industry standard and is widely available. The Solarmeter 6.5 is a prized tool for any serious chameleon keeper and this makes an excellent gift for the chameleon person in your life!