<Table> <Tr> <Td> Lightweight summer duvet: </Td> <Td> 3.0 - 4.5 tog </Td> </Tr> <Tr> <Td> Spring / Autumn weight duvet: </Td> <Td> 7.5 - 10.5 tog </Td> </Tr> <Tr> <Td> Winter weight duvet: </Td> <Td> 12.0 - 13.5 tog </Td> </Tr> </Table> <Tr> <Td> Lightweight summer duvet: </Td> <Td> 3.0 - 4.5 tog </Td> </Tr> <Tr> <Td> Spring / Autumn weight duvet: </Td> <Td> 7.5 - 10.5 tog </Td> </Tr> <Tr> <Td> Winter weight duvet: </Td> <Td> 12.0 - 13.5 tog </Td> </Tr>

What is the highest tog rating for a duvet