Nalorac Z-Spec 400 MHz BB-400-10 10 mm s/n 9112-1226 broadband probe with manual (p/n 964 006). Length: 17 1/4 inches. OD: 1 3/4 inches. The 10mm BB400-10 broadband nmr probe has three observation/excitation channels. The probe contains two observation/excitation coils. The outer (DECouple Channel) coil is normally used to decouple the 1H spins and is double tuned to the 2H frequency to facilitate a field frequency lock. The inner coil (OBServe Channel) coil is broadband. This coil is used to observe the X nucleus. Normal operation frequencies for th three channels are as follows: