3/32" chain joining links, Single Speed and 7-speed types
Connex by Wippermann offers 2 main types of joining links to fit 3/32" chains:
Snap On 708 Link
‘Flush-fit’ type joining links for standard type 3/32 chains that can be used for Narrow Single-Speed use or basic 5,6 or 7-speed derailleur type gears.
Colour: Nickel
Compatibility: Connex Standard 3/32" chains 700, 7Z1 and 708 
Spring Clip Link 7R8/7E8
Heavy Duty chain joining ‘Spring-link’ type link for HD Single-Speed or Hub Gear use 3/32” narrow chains. Reusable.
Colour: Nickel
Compatibility: Connex HD 3/32” chains 7R8 / 7E8.