The unusual look of the 7Z1 is down to the aggressive, anti-rust coating and the chain has been specifically designed for hub geared bikes or singlespeeds with narrow sprockets.
It features a snap-on link connector for easy installation. At £10.99 it's a sound investment for any city bike running hub gears and should withstand regular hours locked up outside. With over 115 year of history Connex chains are made by Wipperman, who, amongst others, supply chains to BMW so they should certainly know what makes a good chain by now.