?The KK2.1.5 KK2.1EVO Large LCD Screen Flight Control Board with Protective Case is the updated version of Hobbyking KK2.1.5. All the firmware of the KK2.1.5 can run on this newly designed interface. But KK21EVO has a larger LCD screen for clear and easy-to-read display. Based on Atmel Mega644PA 8-bit AVR RISC-based micro-controller with 64k of memory・ it features an updated gyro system with a very sensitive 6050 MPU. Installation and setup are easier than ever thanks to built-in software. To top it off・ the KK2.1.5 has built-in polarity protection and a fused output for the included buzzer. Don¨t hesitate to get one!                                    Features             The updated version of Hobbyking KK2.1.5<br> All the firmware of the KK2.1.5 can run on this newly designed interface<br> Larger LCD screen for clear and easy-to-read display<br> Based on Atmel Mega644PA 8-bit AVR RISC-based micro-controller with 64k of memory<br> Updated gyro system with a very sensitive 6050 MPU<br> Installation and setup are easier than ever<br> Built-in polarity protection and a fused output for the included buzzer<br> Perfect for FPV multirotor operations <br>                                                            Specifications             IC     Atmega644 PA    <br> Auto-Level     Yes    <br> Input Voltage     4.8-6.0V    <br> AVR Interface     Standard 6 Pin    <br> Signal from Receiver     1520us (5 Channels)    <br> Signal to ESC     1520us    <br> Firmware Version     1.6    <br> Material     PCB    <br> Weight     0.74oz / 21g    <br> Color     Black    <br> Dimensions     (1.98 x 1.98 x 0.47)" / (5.05 x 5.05 x 1.2)cm (L x W x H)     <br>                                                             Package Includes            1 x KK2.1 Flight Controller<br>1 x Connect Wire<br>1 x User Manual<br>