Presair is a leading manufacturer of adjustable vacuum switches. Our field adjustable vacuum switches allow our customers the flexibility of easily setting the switch parameters in the field as driven by the needs of the project. Vacuum switches are designed and manufactured to exacting standards to meet the needs of original equipment manufacturers and instrument makers for low cost, stable switches and good repeat accuracy. Adjustable vacuum switches span the range on increasing vacuum of 2.5 inches of water gauge to 300 inches of water gauge. Click the image above for more details.