<P> Bra - wearers who have difficulty calculating a correct cup size may be able to find a correct fit using a method adopted by plastic surgeons . Using a flexible tape measure, position the tape at the outside of the chest, under the arm, where the breast tissue begins . Measure across the fullest part of the breast, usually across the nipple, to where the breast tissue stops at the breast bone . This measuring approach assumes that the breasts are not so large or pendulous that they sag significantly, making measuring across the fullness of the breast impractical . Only women whose breasts are firm and spherical can measure without a bra . </P> <P> Conversion of the measurement to cup size is as follows: </P> <Table> Measuring cup size <Tr> <Th_colspan="2"> Measurement </Th> <Th> Cup size </Th> </Tr> <Tr> <Th> inch </Th> <Th> cm </Th> </Tr> <Tr> <Td> 7.0 </Td> <Td> 17.8 </Td> <Td> </Td> </Tr> <Tr> <Td> 7.5 </Td> <Td> 19.1 </Td> <Td> </Td> </Tr> <Tr> <Td> 8.0 </Td> <Td> 20.3 </Td> <Td> </Td> </Tr> <Tr> <Td> 8.5 </Td> <Td> 21.6 </Td> <Td> </Td> </Tr> <Tr> <Td> 9.0 </Td> <Td> 22.9 </Td> <Td> </Td> </Tr> <Tr> <Td> 9.5 </Td> <Td> 24.1 </Td> <Td> </Td> </Tr> <Tr> <Td> 10.0 </Td> <Td> 25.4 </Td> <Td> </Td> </Tr> <Tr> <Td> 10.5 </Td> <Td> 26.7 </Td> <Td> </Td> </Tr> <Tr> <Td> 11.0 </Td> <Td> 27.9 </Td> <Td> DD </Td> </Tr> </Table> <Tr> <Th_colspan="2"> Measurement </Th> <Th> Cup size </Th> </Tr>

Whats the difference between d and dd bra size
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