18650 Battery Charging Tray (w/ and w/o BMS)

I got tired of working hard to avoid damaging cells as I pried them out of my commercial one cell holder after charging. That thing was sized for unprotected cells, but even those weren't very easy to remove. So I designed this thing in Freecad for charging one 18650 cell at a time, either an unprotected cell, or one with BMS protection installed... of course with ease of use being a priority. It uses 4x "Keystone 209" battery clips from Mouser:

https://www.mouser.com/ProductDetail/Keystone-E