A uv silicone wristband can transfer its color darker under sunshine when absorbing uv light. It is not only with good looking appearance but also indicating the strength of the uv index. So some uv silicone bracelets made as the indication with the ruler of levels of index. Wearing on the wrist to avoid long time staying under strong uv. So what makes it uv transfer ? The answer is the UV phosphor which usd uv energy to open the sensitive molecular bond and make it jump from low energy to high energy level There will be a change from visible light to visible light, resulting in the chacharity silicone wristbandsnging color from light to dark. It become a uv silicone bracelet when the UV phosphor is put into the silicone mass and produce it a band. where-to-buy-colored-wristbandsbuy-wristbands-online e chemical properties and physical properties fluctuate slightly according to temperature. UV and ozone can easily decompose the silicone. Organic silicon has better thermal stability and resistance to radiation and weather resistance than other polymer materials. It has a service life of up to several decades in the natural environment Silicone is one of the most unreactive compounds. They are resistant to biological aging without rejection of the animal body. As we can see, that why the silicone bracelet so comfortable and durable to wear. Different color of the bracelet has differcharity silicone wristbandsent meanings. Band color white stand for making poverty history. Yellow stand for livestrong. Black and white stand for standing up and speaking up. Blue stand for beatting bullying. Pink stand for supporting knowledge strength. Blue and white stand for one world one cause Blue and green stand for say no to sectarianism. Also a silicone bracelet can be used as a promotional item for entertainment or sport. It is hot sale as a advertisement gift.