what is it?

[Juganought]

http://www.afv-model.com/4711shop/product_info.php?info=p2577_.html

[Manfred]

This is a mechanical cylinder for raising and lowering a crane arm. The lifting power 0 - 45 ° is 500 g and 45 ° to max. Height = 1,200 grams.

Manfred