These traditional "cow" type distillation receivers have three receivers 45° apart. Condensers with lower drip tip inner joints will protrude into the spherical section, permitting the distillate to fall directly into the receiving flasks without running down the inner wall of the receiver. The distribution adapter has a serrated connection for attachment to a vacuum or inert gas source. This complete item is supplied with the distribution adapter, three flasks of the listed size and six CG-110-01 stainless steel springs or Keck Clips.
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.
The CG-1276-20 is listed here as a replacement flask for the 250 mL size. The replacement flask for the 15 mL size is CG-1507-05.
This type of adapter is also called an "udder". Both this and "cow style" refer to the multiple outlets that are reminiscent of a cow udder.