These clips are designed to be used with the Toolcraft ZD-8925 Desoldering gun, 
to keep the cable and vacuum hose together.
They will probably work for other brands too, if they use the same cable/hose sizes.
The cable of the Toolcraft ZD-8925 is 6mm in diameter.
The hose of the Toolcraft ZD-8925 is 7mm in diameter.

There are two styles of clips. One is an “S” curve and the other one a “C”
Personally, I like the “C” clip better, but they both work great.
I used 7 clips for the whole cable and placed them with 150mm spacing (about 6").