Gas cylinder lifting device. 34-second video:
https://www.youtube.com/watch?v=daZZGVFSPRc
Found the patent with a search on the inventor's name at the wonderful but complex US Patent Full-Text and Image Database Advanced Search, with the search query: IN/(guerrero AND fred) AND APT/1. That's IN for inventor name, and APT/1 means utility patents, as opposed to design patents or plant patents.
Gas Cylinder Lifting Device by Fred Guerrero - US Patent #8,833,821
https://diqn32j8nouaz.cloudfront.net...ing_device.jpg
More: https://attollolift.com/
Previously:
https://www.homemadetools.net/forum/...568#post117613
https://www.homemadetools.net/forum/...608#post139591
https://www.homemadetools.net/forum/...616#post102044
