I got a replacement air filter (my moped was sold to me without one) and it consists of a plastic box and a round hole with a wire mesh where the filter attaches to the carburetor. The filter was sold as one made for my moped (1978 Vespa Bravo)
So my dad tells me there should be more than a wire mesh between the outside world and the engine, like a sponge or foam to catch tiny dirt particles, in other words the filter might be missing something. Is it true that these filters have more than the mesh to them? Should I complain about missing parts to the seller? I bought the filter on ebay.