It is also commonly done from parallel two-faced lines.

Note that in the case of parallel two-faced lines, the leaders (the dancers facing out) are moving closely together, even though they are doing two separate actions. (The end dancer is doing a Circulate, while the center dancer is doing a Trade.) In this case, some dancers prefer to maintain their hand-hold and walk together as a couple.

But it can be done from any formation where there are two pairs of centers who can Trade, and four end dancers who can Circulate around the outside.

The Trade in the center can be a Partner Trade, and the Circulate around the outside can be a facing Circulate.