These coaxial shorts are useful to establish a reference plane, as well as providing certain protections from the environment. SMA shorts and Type N Shorts can establish reference planes. These coaxial shorts are not VNA grade but are often used at lower frequencies for calibration purposes. Included here are the following shorts: 2.4mm, 2.92mm, 2.2-5, BNC, N, SMA, SMB, SMP, SSMA, SSMC, TNC. Note, more options: 1.85mm is compatible with 2.4mm, 3.5mm is compatible with 2.92mm.