Info on the Uber-thin condoms says they are made of latex.
Ansell makes another condom called Lifestyles Skyn, which is non-latex. But it is NOT made from polyurethane. It is made from polyisoprene, which is more similar to latex, but transmits heat like poyurethane. Thickness is the same as an average latex condom - 70 microns.
Trojan Supra is made from polyurethane and is 40 microns thick. I have tried them and like them. I had a lot of problems with them breaking, but that was when they came with a spermicidal lubricant, but since theybegan making them without the spermicide, that has not been a problem.
Durex Avanti made a polyurethane condom, but I had problems with them breaking, and like Trojan Supra better. But just recently, they have switched from polyurethane to polyisoprene in their new Durex Avanti Bare condom. These are as thin as the latex Uberthins, but not latex. Made from same material as Lifestyle Skyns, but thinner, only 50 microns. Have not tried them yet, but am very curious to compare them with the Trojan Supras.