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Understanding how neuronal activity supports behaviour remains a challenging question in neuroscience. Electrophysiological extracellular recording in freely moving animals is a powerful tool to observe the relation between the activity of populations of neurons and the behaviour of animals performing cognitive tasks. Neuropixels probes [1] were developed for simultaneously recording the activity of hundreds of cells from multiple brain regions. The 10 mm long silicon shank (with a cross-section of 70x20 µm) contains almost one thousand integrated switchable electrodes of which 384 channels can be addressed in parallel. The small cross-sectional dimensions and long fragile shank necessitates, very careful handling of the probe. Permanent fixation of the probes to an animal’s skull in chronic experiments limits reusability. To overcome those limitations, we have developed 3D-printed implants to facilitate the use and re-use of Neuropixels probes in freely behaving rats and mice. The key features of the design are: 1) lightweight allowing free behaviour of the animal, 2) implantation of multiple Neuropixels probes in chronic preparation, and 3) a straightforward re-use of the probes. The implants have been successfully used to record the activity of neuronal populations over weeks. By using these implants, Neuropixels probes and similar devices will become more accessible to the broader neuroscience community and the relative costly active probes can be used for several chronic experiments. [1] Jun J.J. 2017 Fully integrated silicon probes for high-density recording of neural activity, Nature 551, 232-236