Features: Brand new and high quality Use 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:ABS Operating voltage: 5-24VDC Working current : 6-8MA Power interface : 2.1mm x 5.5mm Female Male Power socket Voice interface : 2x 3.5mm socket MCU input interface : 7x 2.54MM pin header Size:Approx.63x40x13mm/2.48x1.57x0.51inches Package Includes: 1 Set Generator Encoders Transmitter 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.