Print this bottom to allow integration of a kobalt 24V battery to the 18V ryobi tool. Use the top part from the linked model for the RYOBI half. For terminals on the kobalt half Use spade terminals or appropriate ring terminals and glue/melt in place. The ryobi contact can be made from hammering flat some 14-12awg copper.. Bend appropriately and then solder your wire to them. positive is marked on the model. 4mm 4x20 or #8 flat head screws hold them together. For the spring some small 9mm od silicone hose trimmed to about 5mm works well.
The author remixed this model.
not so much a variation but an adapter to allow part of the old ryobi/milwaukee model to work with the lowes kobalt 24v ecosystem batteries.