About this item Screw terminal for External power Supply (with Jumper Select Option) and External Power Supply range of 7V to 20V with 7805 on board for Internal +5v Supply Compact and Ready to use design and Professional Glass PCB Layout Design for Noise Reduction with Board Supports ATmel 8051, 8052, 8032/31 Series Microcontrollers On board Two Line LCD Display (2x16), Two multiplexed 7-Segment LED Display, Built in Switches (8 keys), Built in 8 LED Interface to test I/O, on Board Reset buttons, Bluetooth Interface (HC-05), Buzzer All Port 32 Pins are Breakout Pins are available at male bugs Connector which can be used as main board for developing applications