All Bird Plug-In Elements (slugs) are calibrated in accordance with meticulous Bird calibration procedures supported by a long history of mean deviation values to assure adherence to advertised specifications of current instruments, as well as field interchangeability with equipment purchased, used and trusted in all the years since its introduction.
7/8" Plug-In ElementsElements for 7/8" line sections and wattmeters
1-5/8" Plug-In ElementsElements for 1-5/8" line sections
3-1/8" Plug-In ElementsElements for 3-1/8" line sections
4-1/16" Plug-In ElementsElements for 4-1/16" line sections
6-1/8" Plug-In ElementsElements for 6-1/8" line sections