Stitching Needle

[susiek]

I came across this in a box of stuff, it is FANTASTIC for saddle stitching - but I have no idea what it is called, it has a for lack of a better word, sheath over the needle, that slides up and locks the thread in place.  The sheath does not fall off at the end either.   Its great and a time saver, has anyone ever seen one of these and/or know what its called.  My dad did leatherwork for years, he's gone, don't know if this is something he came up with... or if it is actually available.. to much time spent searching had to reset my  password here, so here it is.