A bracelet (100, 200, 300), with: a detecting apparatus (101, 201, 301) for detecting a blood count parameter of blood in a blood vessel of the arm, said detecting apparatus (101, 201, 301) having a transmitter, which in turn comprises: - a number of transmission antennas for transmitting at least one transmission signal, - a receiver having a number of reception antennas for receiving at least one reception signal, - a processor configured to select: a first detection configuration comprising a transmission antenna of the number of transmission antennas and a reception antenna of the number of reception antennas, and a second detection configuration comprising a transmission antenna of the number of transmission antennas and a reception antenna of the number of reception antennas, - when the first detection configuration is selected, a loss detector configured for transmitting a transmission signal in order to detect a first loss quantity on the basis of the transmission signal and the reception signal, and when the second detection configuration is selected, for transmitting a transmission signal in order to detect a second loss quantity on the basis of the transmission signal and the reception signal, wherein the processor is configured for selecting a detection configuration by comparing the detected first loss quantity and the detected second loss quantity to detect the blood count parameter, and an adjusting apparatus (103, 203, 303) for adjusting a predetermined contact pressure of the bracelet on the arm, the bracelet (100, 200, 300) being designed as an inflatable bracelet. a detecting apparatus (101, 201, 301) for detecting a blood count parameter of blood in a blood vessel of the arm, said detecting apparatus (101, 201, 301) having a transmitter, which in turn comprises: - a number of transmission antennas for transmitting at least one transmission signal, - a receiver having a number of reception antennas for receiving at least one reception signal, - a processor configured to select: a first detection configuration comprising a transmission antenna of the number of transmission antennas and a reception antenna of the number of reception antennas, and a second detection configuration comprising a transmission antenna of the number of transmission antennas and a reception antenna of the number of reception antennas, - when the first detection configuration is selected, a loss detector configured for transmitting a transmission signal in order to detect a first loss quantity on the basis of the transmission signal and the reception signal, and when the second detection configuration is selected, for transmitting a transmission signal in order to detect a second loss quantity on the basis of the transmission signal and the reception signal, wherein the processor is configured for selecting a detection configuration by comparing the detected first loss quantity and the detected second loss quantity to detect the blood count parameter, and - a number of transmission antennas for transmitting at least one transmission signal, - a receiver having a number of reception antennas for receiving at least one reception signal, - a processor configured to select: a first detection configuration comprising a transmission antenna of the number of transmission antennas and a reception antenna of the number of reception antennas, and a second detection configuration comprising a transmission antenna of the number of transmission antennas and a reception antenna of the number of reception antennas, - when the first detection configuration is selected, a loss detector configured for transmitting a transmission signal in order to detect a first loss quantity on the basis of the transmission signal and the reception signal, and when the second detection configuration is selected, for transmitting a transmission signal in order to detect a second loss quantity on the basis of the transmission signal and the reception signal, wherein the processor is configured for selecting a detection configuration by comparing the detected first loss quantity and the detected second loss quantity to detect the blood count parameter, an adjusting apparatus (103, 203, 303) for adjusting a predetermined contact pressure of the bracelet on the arm, the bracelet (100, 200, 300) being designed as an inflatable bracelet.