4XF0G88935 - Lenovo 3.5-inch 5.25-inch Converter Kit Tray for ThinkServer TS150, may fit other Lenovos but you would need to confirm this yourself. I have four of these, and have used one which I took photos of, so the ones I am selling are all BNIB and still with their original seal. I used one of these to take the empty 5.25" drive space in my TS150 ThinkServer and fit a 3.5" disc. This allowed me to fit 4 HDD for a NAS I was building.
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