well, half of the locking-knobs aren't properly attached to the locking-screws,
they just came off as I tried to loosen the locking-screws.
this made winding the higher 3 strings kind of a pain in the butt
I worked it out by loosening the screws with a pair of tongs.
I was then able to turn the locking-scews open and ( after reattaching the turning-knobs ) close them properly
I won't send them back, because this is easy & cheap enough for me to fix at home, also, it's a minor malfunction for something I will use about once / twice a year
otherwise they work great
wish they could've been black, but the silver isn't bad
easy & obvious enough to set up for me
( no manual is included anyway )
if you're unsure;
just retrace the steps of deconstruction and do it backwards ;)