Yes. This klf 20/30 pic shows the 'threaded cabinet insert' . It is metal. It's threads extend/screw about one inch into cab base. It has a threaded hole in it's center - end to end of the 'insert'. Threaded central hole is for spike cover and spike itself.
The vinyl cap is i suspect what functions as a foot, as alternative to spikes.
I have pretty good idea how spike (klf) system works.
How the 'vinyl cap' looks and how it attaches to the 'insert' is not clear to me.
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