Well I have a very well broken in SuperTool sheath and I tried it the other day and guess what the Core barely squeezed in there I would say with some water and some time I could probably get it to work fine But no go with any accessories I was thinking of putting my ST300 in it after I tried the water and stretched it with the Core but I have an adapter as well and don't know if I want to part with it so easily All in all it's possible but would be much harder for a new Supertool sheath I would imagine