The Thermo Scientific Velos Pro offers resolution up to 100,000 FWHM and mass accuracy better than 1 ppm RMS, providing confidence when analyzing complex samples. Multiple fragmentation techniques - CID, HCD and optionally ETD - provide versatility and facilitate structural characterization. Fast scanning and parallel MS and MSn analyzes accelerate analyses. Ion optics with new neutral blocking technology increases robustness. A collision cell with an axial field gradient improves quantitative results. High mass resolution and mass accuracy enable accurate molecular weight determination of intact proteins, identification of peptides in complex samples, and analysis of isobaric species. High sensitivity enhances the detection of low-abundance peptides and proteins. A short duty cycle increases sequence coverage within a single experiment. Stability, mass accuracy and a wide dynamic range facilitate label-free quantification. Mass resolution and mass accuracy distinguish between heavy and light peptide ion pairs and interference in SILAC experiments. An axial field HCD cell improves the quantification of isobaric labeled peptides. Optional electron transfer dissociation (ETD) provides complementary information for PTM analyzes and de novo sequencing. This Thermo LTQ MS includes a vacuum pump and a PC and can be ordered with an Orbitrap, an HPLC front end and other accessories. Labprocure is responsible for this device.