These items are similar to the CG-1279, but the top outer joint is vertically oriented instead of being at a 105° angle. The complete item consists of a vacuum adapter, distribution adapter, four of the listed size flasks with hooks and ten CG-110 stainless steel springs. It uses the corresponding distribution adapter as the CG-1279; only the vacuum adapter is different.
Application note: Some vacuum distillations need to be performed at a specific pressure rather than full dynamic vacuum. To maintain a relatively low vacuum (~2-50 torr), once can use an adjustable bubbler such as item #AF-0513-A-21 as a low-tech vacuum control (manostat). For those situations where you need to operate at pressures as high as 760 torr or want to avoid the use of mercury (a good idea), consider a Mano-Watch™ vacuum controller/monitor, item #20900-A.