I have never understood why the vast majority of strap pins were conical. These larger flat ones make a lot more sense because the strap is much less likely to slip off of them. They are not that much larger than the regular ones (by only a couple of millimeters), but, combined with their improved geometry, that slight increase in size is more than enough to make a world of difference! To someone like myself who never performs acrobatics with their instruments, these strap pins more or less eliminate the need for strap locks; and the fact that they are very well made and do not cost a fortune is an added bonus.