Potassium chloride is used to kill people.
It is used for lethal injections ... AND ... it is NOT DETECTIBLE, postmortem:
Potassium chloride intravenous injection is used in ... lethal procedures for state-sanctioned punishment.
Owing to its relatively high concentrations in hemolyzed blood (25-80 mM) compared to serum (about 4 mM), it is difficult to conclude potassium poisoning by postmortem analysis of biologic samples.
https://pubmed.ncbi.nlm.nih.gov/21923800/
It is also used in the Pfizer Covid (so-called) vaccine:
Here's the complete list of ingredients, according to Pfizer-BioNTech: ... Potassium chloride
Did Pfizer disclose the amount of KCl used in the (so-called) vaccines? No.
Did Pfizer disclose whether or not different amounts of KCl was used in different vials for different individuals? No.
KCL is commonly given IV to replace low K levels in blood.
The amount used in any vax would be well below any lethal amount.
Well... You say that, but we already know that ingredient potency was not consistent.