Product review (1 stars): Stems crack after a few months of use.
Piece of junk.  LG should be ashamed of this design.
The replacement knobs worked great for 6 months and then the plastic stem cracked leaving them loose and wiggly. I will find a suitable brass tubing to slip over the stem and epoxy it in place to get some more life from these expensive replacements.  Hope someone sues LG when they fall off with the burner still on (no injuries I hope).  We remove them when using the broiler so the silver finish does not blister like the originals did after a year. Still might be a problem if opening the oven when very hot.  Used to be a guy that sold all metal replacements $$$, but apparently no longer does.