Mr. Baxter --

The only tag affixed to my US Engines says "006956". There is no other tag affixed and the engine is still new - that's the way it came from Tower Hobbies. So how else, other than disassembling the engine and measuring, can one tell exactly what size this engine is? If by chance I were to want to sell it in the future, how would I prove to someone exactly what size it is?

Thanks for your help.