This unit is prebuilt. selling because i want to upgrade. Has raspberry pi os. works great. has cooling fan.
See here:
https://www.amazon.com/RasTech-Raspberry-Active-Screwdrive-Included/dp/B0FNBYQWX3/ref=sr_1_3?crid=1M0EZ6TYX9U7V&dib=eyJ2IjoiMSJ9.n20rBKR0UOhmTWzNCpRSE6LBFJd6dQnaH9CGuf4u_3EcCobemNprOYp-7DyNzn3f7RaIcFuSA9vOiyq9EahIXZMa8BNB1R_NdXaY2vSgM4ND2S0tODI6PleI9slk4mmZxHxwV0WJMokTKSXw1gU-PpoA5qubrZ7OngcCDs_hrbQcd-FjYiu0BYvv_OoOxLGciyBZ5pwCm0h38alvlBoEMSojlQkCRTXeDJqzyd6-FnU._4xOHFskt97rgaF8A3h2b5kl27rRHqAlYYJI0KFPfoE&dib_tag=se&keywords=raspberry+pi+5+4gb&qid=1783897714&sprefix=raspberry+pi+5%2Caps%2C200&sr=8-3