This is the sign for a zipper merge in Germany: https://www.swr.de/-/id=22217882/property=gallery/pubVersion=1/d6vtby/r.jpg https://www.swr.de/-/id=22217882/pro

This is the sign for a zipper merge in Germany: https://www.swr.de/-/id=22217882/property=gallery/pubVersion=1/d6vtby/r.jpg https://www.swr.de/-/id=22217882/property=gallery/pubVersion... (the text says "zipper merge, no sooner than in 400m"). But we also have the arrow sign you describe, albeit with the same text as the other one: http://www.steine-und-erden.net/se501/reissver.gif http://www.steine-und-erden.net/se501/reissver.gif. It would be interesting to conduct a study on whether there is a change in behaviour depending on which sign is used.