If you want to start casting in your shop, this Master-cast is a great unit for you. The Stuller Master-Cast is perfect for a small or medium shop.  The Vacuum investing is accomplished under a “9 by 8” bell jar.  The unit will accommodate perforated flasks as large as 5 inches by 7 inches.   A direct drive, two-stage pump and motor create a free air displacement of 3 CFM.  The unit’s vacuum exceeds the required 29.9 inches of mercury, in less than 1 minute.  Order this unit today at  Stuller.com/tools.