Convenient And Intelligent Design All to one design: Such a design can make you taking it more easier . Built-In Trumpet Or Earphone: You can listen the fetal heart by built-in trumpet or earphone. The host embedded rock can achieve many people listen the fetal heart sounds at the same time instead of using the external accessories Power Support: power with dry batteries AAA Advanced technology Split-Type Design. separate design between host and probe to be convenient for finding the place of fetal heart sounds Angelsounds To Remote Central Monitoring System. It can be used singly and also transmit the fetal heart signal to the Remote Central Monitoring System in hospital through ordinary monitoring telephone to provide diagnosis for doctors, enjoying the hospital experts' diagnostic services at home. Angelsounds To PC . Can transmit the real-time sound of fetal heartbeat sounds to the computer saving for memory by specialized data lines Specification: Utrasound frequency : 3.3 MHz Acoustic intensity: < 10mW/square centimetre Peak negative pressure: <1 Mpa Output beam intensity: <20mW/square centimetre Dimension: 21cm X 16cm X 8cm Standard: CE, EN ISO9001:2000, EN ISO13485:2003, TUV