Just like a regular underwire, a floating wire is also located in the bra cups. It improves the fit and support that the bikini or bra provides. However, it is not secured to the frame of the brassiere. Thus, it gives you the convenience of removing the wire in the future if need be. In a regular underwire bra, the same wire is secured inside the concealed hem. So, it is not removable. This makes floating underwired bras slightly pricier. However, they are comfortable, too, so you can take them into consideration while purchasing underwired bras.