This 5-in-1 engineering construction toy 3 boy old toy year comes with a manual drill and allows for free disassembly, assembly and interchange of parts. It can be used to build 5 types of vehicles such as a water tanker, mixer truck, excavator, crane, and sand truck. With the illustrated manual, it is easy to get started. As a Stem educational toy, it can help children develop their hands-on skills, hand-eye coordination, patience and problem-solving abilities, and stimulate creativity and imagination. It is suitable for parents and children to assemble together, with strong interactivity and lots of fun. The operation is simple and it is suitable for boys and girls aged 3-6 and above. It is an ideal gift for cultivating hands-on and engineering interests.