This is a clone of an "PureThermal 1". I used a Lepton 3.5 sensor out of an broken Flir One Pro. The shipped "purethermal1-firmware" v1.0.0 is working fine! If you like to compile a newer firmware from the original sources just uncomment in /src/main.c ->> //PT_SCHEDULE(button_task(&button_task_pt));. Without the competent and open support of the seller this update wouldn't be possible for me! Thank you