From early fall to late spring and sometimes like now a bit beyond, villagers come to Belgrade to sell wool sweaters, socks, and caps. They're wonderfully warm, and generally not so expensive. They make great souvenirs. This man is trying one last time, or so I imagine, to sell his wares rather than keep them for next year.
The town of Sirogojno (SEE-ro-goy-no) is famous for its fabulous sweaters. Unlike this man's, they're quite pricey, but just about everyone I know who lives here for a while has splurged on one, this writer included. Here's a link.