Features:Brand new and high qualityUse for home, office and industry electrical.The module can instruct MCU(or keyboard)to generate 16 two fold tones from 1/2.The module is unintentional for dialing keyboard and MCU interface.Strong material ensures strength and durability for long lasting usage.Wide voltage ranges,you can connect it from 5-24VDC. Specifications:Material:ABSOperating voltage: 5-24VDCWorking current : 6-8MAPower interface : 2.1mm x 5.5mm Female Male Power socketVoice interface : 2x 3.5mm socketMCU input interface : 7x 2.54MM pin headerSize:Approx.63x40x13mm/2.48x1.57x0.51inches Note:1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package includes:1 Set Generator Encoders Transmitter