I didn't use it for long enough to be able to say if it provides substantial sun protection. But when it says it's an oil, it means it and it shows. It has the exact same texture and greasiness as sunflower oil and it makes everything oily. Then you need to wash it off. Seawater doesn't do anything to it... which I hope means that it provides longer protection. My hair is particularly dry and it reacts to the use of oils like coconut oil or shea butter without looking greasy, even as a substitute for silicone or leave-in moisturizer. But this product managed to make them oily. Unfortunately, it didn't manage to moisturize them at all. I will use it hoping that it offers some of the sun protection it promises, but exclusively only at the beach