OEM Bosch Air Flow Meter AFM 0 280 200 020 VW Volkswagen Bus 1977 1978 1979. Looks like a piece is broken inside (see pic).
This item is in the category "eBay Motors\Parts & Accessories\Car & Truck Parts & Accessories\Air & Fuel Delivery\Air Intake & Fuel Sensors". The seller is "702jimmy1967" and is located in this country: US.