The 3F series quadrupole mass spectrometers from Hiden Analytical Ltd. now feature direct digital signal detection that provides fast response and sensitive detection levels. Designed for research in the ultrahigh-/extremely high vacuum regime, they also are suitable for use in specialized fast-event gaseous studies at pressures to atmosphere and beyond. The 3FD system integrates triple-stage mass filter technology with digital data acquisition by direct positive ion counting (pulse counting). This combines a continuous detection range of seven full decades with a detection rate from just one ion per second and abundance sensitivity measurements to the parts-per-billion regime. The integral data accumulation mode enables operation with time-functioned data acquisition for suppression of fundamental ion statistical noise.