Box opened but all pieces and parts are present except for the 1.5mm hex screw driver. The Teching DM135 Small Bypass Turbofan Engine Metal Mechanical Model Kit is a high-quality unassembled kit designed for engineers and hobbyists aged 16 and above. This model kit features a Turbofan engine subject, with a focus on mechanical and metal materials. The kit offers a hands-on learning experience for assembling and understanding the inner workings of a Turbofan engine.