Germany. The Unicoupler/Intermat coupler can automatically couple two pneumatic lines and up to six electrical connections. This coupler is mechanically compatible with SA-3 and Willison couplers (but pneumatic and electrical connections must be done manually). The Unicoupler is also known as AK69e. Maximum tonnage of a train that uses this type of coupler is about 6000 t. AK69e and Intermat adoption failure has been attributed to economic performance. it has found limited use, it's been adopted by the Iranian Railways and is also used in Germany on trains transporting iron ore between Hamburg and Salzgitter. C-AKv The C-AKv coupler (also called Transpact) is a newer compact Willison coupler developed by Faiveley Transport. It is mechanically compatible with the SA3 coupler (but pneumatic and electrical connections must be done manually), fully compatible with the Unicoupler and, if additional buffers are mounted, it can be coupled with the conventional European screw coupling as well. The C-AKv coupler can automatically couple two pneumatic lines. its use is limited to trains transporting ore between Rotterdam and Dillingen steelworks and lignite between Wählitz and Buna in Germany. Z-AK The Z-AK coupler is yet another Willison coupler developed by Knorr Bremse. It was designed in response to the obvious failure of the Unicoupler/Intermat. It is compatible with the buffers and screw coupling. It is one of only few automatic couplers that cannot carry tensile forces, railway vehicles using this type of coupler must be equipped with buffers as well. Unilink coupler The Unilink coupler is a coupler compatible with SA3 and screw coupling, which is used e.g. in Finland. It is an SA3 coupler with an additional horn that allows hooking up of the chain, and also with an adapter that connects the hook to the SA3 head. Rolling stock equipped with Unilink couplers is also equipped with side buffers. Multi-function couplers Multi-function couplers (MFCs), or fully automatic couplers, make all connections between the rail vehicles (mechanical, air brake, and electrical) without human intervention, in contrast to autocouplers, or semi-automatic couplers, which just handle the mechanical aspects. The majority of trains fitted with these types of couplers are multiple units, especially those used in mass transit operations. There are a few designs of fully automatic couplers in use worldwide, including the Scharfenberg coupler, various knuckle hybrids such as the Tightlock (used in the UK), the Wedgelock coupling, Dellner couplings (similar to Scharfenberg couplers in appearance), BSI