Update: Refer to this article regarding the current shape of the STEMFIE nuts
Recently the community asked for an easier way to locate the spanner tool on the nuts, and now a new version of the device has been improved.
Several users have pointed out that the two basic types of fastening nuts in the STEMFIE standard, the cam-locking, and the threaded nut, are too similar, seen from the outer shape. Therefore, a new version of both nuts was made and is now available for download from the STEMFIE file repository or by clicking on the links below.
The difference between both markings is that the nut with the traversal line is threaded; the nut with the longitudinal line is of the cam-locking type.
Thanks to the community for testing STEMFIE and suggesting improvement! :-D
This toy is unsuitable for children under three years due to choking hazards! 
