Nude Bayard-Alpert Ionization Vacuum Gauge, <3 x 10^-11 - 1 x 10^-3 Torr, Dual Thoria-coated Iridium Filaments, 2.75 in. CF, Pin Guard

The 274042 Nude Bayard-Alpert Hot Cathode Vacuum Gauge features dual thoria-coated iridium filaments for a <3 x 10^-11 - 1 x 10^-3 Torr vacuum measurement range, and has a 2.75 inch non-rotatable CF flange fitting with pin guard. Bayard-Alpert (hot cathode) gauges provide pressure measurement based on the ionization of gas molecules by a constant flow of electrons from a filament. The number of ions created is directly proportional to the density of molecules. The ions are collected and measured by a vacuum gauge controller and converted to pressure based on the sensitivity of the gauge. nude Bayard-Alpert hot cathode vacuum gauges are the best solution to severe ionization gauge pumping problems.