Batteries for Philips wireless headphones
Actually, look at the Philips SBC HB550S battery, the black label on battery isn't going to the end of the battery's "-" side, there's few millimetres of solid metal. Look at other, ordinary rechargeable battery, for ex duracell's. This other battery has label all over battery (from "+" to "-"). So only thing you have to do to make any batteries work with you have to cut and remove this label from battery you want to use from the "-" side of the battery, about 1-2 cm, like philips one has. It's because these headphones have this extra clip in battery sockets, philips wants us, customers, to buy those extra-expensive batteries. That's as simple as it is! Hope it helps you, it definitely helped me.