Features: 1.The product is suitable as for middle school physics experiment teaching instrument 2.Used to explain the basic structure and working principle of 4 stroke single cylinder diesel engine 3.Provide two ways of use, manual or battery connected to the power supply 4.This model is already assembled, no need to install by yourself, more easy to use 5.Come with compact design, easy to demonstrate, which make students understand better specification:Item Type: Gasoline Engine Model Material: Engineering plastic Function: Used to explain the basic structure and working principle of four stroke single cylinder diesel engine. Size: Length: Approx. 29.3cm / 11.5in, Width: Approx. 16.7cm / 6.6in (manual measurement, for reference only) Battery Model: 2 x AA batteries (not include) PackageList:1 x Gasoline Engine Model