This file is from Wikimedia Commons and may be used by other projects.
The description on its file description page there is shown below.
Summary
DescriptionZ-pulley.jpg
English: The final drills of the day were the preparation of C-pulley rescue systems and then their conversion to Z-pulleys.
All of these skills require constant practice and reinforcement or they will be of little use in a real emergency.
This image was originally posted to Flickr. Its license was verified as "cc-by-sa-2.0" by the UploadWizard Extension at the time it was transferred to Commons. See the license information for further details.
to share – to copy, distribute and transmit the work
to remix – to adapt the work
Under the following conditions:
attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.