low temperature stirling engine educational toys toy model kits
* Wheel Color: black
* Wheel Material: ABS
* Wheel diameter ：78mm
* Cylinder diameter ：90mm
* Cylinder material : Stainless steel
* piston material ：High purity graphite ，sponge
* model size : 90mm*100mm(H)
* model weight :158g
* Attention ：
prohibit add water .lubricating oil into the cylinder !!!!!
* it will running on your warm hand ,on the hot water cup ,it is a very interesting puzzle science education toy model or a gift for your children , your friends and your family member !
* about shipping :
Even if you select economy shipping , we will still ship by SPEEDPAK standard or standard shippng , with tracking number and tracking info .