The 24 series are 3/8 offset shorts are banded waveguide components used for waveguide calibrations. Waveguide calibrations require an alternative calibration than a coaxial SOLT (Short-open-load-thru) because an open waveguide standard is generally not very reflective so the use of offset shorts is generally accepted as a substitute. Waveguide calibrations that use offset shorts include SSLT (Short-short-load-thru) and LRL/LRM (Line-Reflect-Line/Match).