20BPG-100 (05703161): B-Series Pressure Murphygage Pulsation Dampeners They have a slotted sensitivity

They have a slotted sensitivity adjustment located on the side of the case (see drawing)

Inside the A20DP-K-30

A set of contacts is held in a latched position through a magnetic latch mechanism

Murphy's PD2160 pulsation dampener

The 20V-30 Vacuum Swichgage is commonly used to measure loading of spark ignition engines through intake manifold vacuum

20BPG-100 (05703161): B-Series Pressure Murphygage Pulsation Dampeners They have a slotted sensitivityThe 20BPG 100 B Series Pressure Murphygage is a high quality, diaphragm actuated indicating gauge, with a pressure range of 0 100 psi. Built with the same heavy duty design as the standard 20 Series Swichgage instrument, the B gage is more compact and is the optimum instrument for gauge only applications. The 20BPG 100 has a high impact polycarbonate lens, a sturdy environmentally sealed steel case, and a polished, low profile stainless steel bezel.